User:Vili/thief

So You Want To Be A Thief

I suggest at least glancing at the Thief article if you're new, since I'm not going to get into all the basic details such as profession mechanics, etc. here. If you already know the class in general and just want some quick advice on builds, skip to the end.

I also highly recommend looking at the official forums post compiling bugs on the Thief class. It's not as well organized as other threads, but it is stickied at least. Some of the things I say here might be flat-out wrong due to bugs, although I try to update this as I learn more.

Last updated: Vili 点 00:57, 5 October 2012 (UTC)

Overview

The Thief is a PvP-oriented class that focuses on burst damage and mobility. PvE is not totally impossible as a Thief, but it certainly isn't the cakewalk that e.g. Ranger is. You'll need to pay attention to your aggro, how many and what things you pull, relative positions of allies and foes, terrain, and other factors to be at peak performance. One particular disadvantage of the Thief for PvE is that the defensive skills all rely on avoiding attacks rather than blocking/redirecting them; unfortunately, this means that against foes with unavoidable attacks, or with attacks that are difficult to predict, the Thief is quite vulnerable. Compare this to, say, a Guardian - Guardians have many damage mitigation abilities that don't require them to move around at all (or, actually, encourage them to sit still and take a hit). This is especially noticeable when playing with less-than-stellar FPS or Internet connection, since one failed dodge on a Thief can mean instant death.

Either way, if you're a lazy player that doesn't want to/can't expend a lot of energy and effort, Thief probably isn't the class for you; you can make decent progress because the Thief is an inherently powerful class, but you're never going to be a master player. To put it succintly, Thief is a high-risk, high-reward class that will only give back as much as you put in.

(As with any MMO, there will always be certain cheesy builds that completely trash stuff in PvP with minimal effort, but I'm not going to get into such things here because I want to encourage players to be actually good at the game.)

Strengths and Weaknesses

Thieves are good at:

• Mobility. The Shadow Step mechanic allows a Thief to travel great distances quickly, closing the gap between opponents or retreating from battle as necessary. Thieves also have many ways to either improve their own speed or slow down their opponents; several snaring options are available. Most notably, Signet of Shadows passively grants 25% faster movement speed both on land and underwater. This is one of the best speed boosts in the game, since it can be maintained indefinitely, can't be removed, and isn't conditional at all.
• Burst damage (mostly against single targets). The Initiative mechanic means that a Thief's weapon skills have no real cooldown; this enables them to blow all their attacks at once for a spike of high damage. Combine this with the already very high attack speed of Daggers, or the slower but harder-hitting Sword (notably Pistol Whip), and the Thief starts to look a lot like an assassin. Even the Pistol can produce decent damage numbers, although being a ranged weapon it suffers a number of other drawbacks such as being completely mitigated by projectile reflection.
• Battle flexibility. A Thief can adapt quickly to new situations as the battle calls for it; unlike some other classes, a Thief can switch between ranged and melee combat without needing two totally different setups for each, and can be good with both. This is because the Thief's utility skills are mostly weapon-agnostic; they are equally useful no matter what weapons are equipped at the time. The weapon skills have everything the Thief needs for that weapon.
• Maintaining Bleeding, Poisoned, Blind, and/or Weakness indefinitely (or at least for a long time) with minimal effort. Throw in Cripple with the right utility skill. More on this in later sections.
• Generating uncommon, powerful combo fields. It's very easy for a Thief to create the Dark Field, Poison Field, and/or Smoke Field without having to take rare skills that compromise a build. The Dark Field is otherwise only possible with a Necromancer, a class that (according to official statistics) is not hugely popular. Poison Fields come from two particular Necromancer skills, an Asura racial, an Engineer utility skill, or some Ranger pet skills on long cooldown; using the Shortbow, a Thief can generate Poison Fields all day long. The Smoke Field is only available from two Engineer utility skills and one Ranger pet skill on long cooldown (and then only underwater); Thieves get it with the off-hand Pistol, meaning no recharge, or one of the better utility skills.

Thieves are bad at:

• Healing allies and removing Conditions on them. The only way a Thief can heal allies is by casting Shadow Refuge (one minute cooldown, small heal) or by traiting for Shadow Protector, which heals allies if the Thief applies Stealth to them. Even then, it's only five seconds of Regeneration, and the skills that stealth allies are on long cooldowns. The Thief has exactly one way to remove conditions from others, and it's a mediocre signet utility skill with a weak passive. It only removes one condition from allies, anyway...in this game, where there's one condition, you'll usually find more, and there is no way to pick exactly which one you'll be removing either.
• Tanking/taking hits. Although Thieves can keep up Blind for a long time, this is ineffective against bosses with Unshakable, since it will only work 10% of the time. The more powerful Blind skills also require the target to sit still in the area of casting, which doesn't always happen. Thieves also have only two ways to Block attacks, one of which only works underwater, and the other only works on projectiles. There are a variety of skills that let the Thief Evade; however, some of them fail at random times and others are on long cooldown or are so important that they can't just be blown whenever. Finally, the Thief doesn't have access to heavy armor, Shields, or skills or abilities that improve armor, health, etc. The exception is Practiced Tolerance, but that only grants 5% of Precision as Vitality, which is okay but not nearly enough to make a Thief non-squishy.
• Buffing allies/doing support. A Thief's biggest contribution to allies is to generate combo fields and kill/disable stuff. While they can grant a few offensive Boons with particular traits, they can't do it very often. Boons are just not really a Thief thing. There is one particular build that uses Venoms to buff allies, but it still isn't as effective as e.g. a Guardian would be for support.
• AoE damage. Swords hit things in the swing area, but this is relatively small and also suicidal against huge groups/really strong enemies (unless the Thief isn't being targeted for some reason). The Shortbow deals decent AoE damage at range, but it's mostly damage over time rather than burst, so it kills pretty slowly. Pistols have no AoE damage at all, unless one traits for Ricochet, which is really bad. Daggers only hit one target with the swing, period; there are two Dagger skills that deal AoE, but one of them isn't really meant to deal damage and the other costs a lot of Initiative. Underwater, the Spear has swing AoE, and Nine Tailed Strike is also AoE, and the Harpoon Gun can pierce in a line. Thieves are out of their element underwater, though, so...Only one Thief utility skill deals good AoE damage, but that is entirely due to Bleeding and therefore also kills slowly. Dagger Storm, one of the Thief elite skills, deals heavy AoE damage...but it's somewhat unpredictable, and being elite, it has a long cooldown. Finally, aggroing many things at once is just not a good idea for a Thief in PvE, so even with good AoE skills they wouldn't be smart to use a lot of the time.
• Underwater combat. Most of the good Thief utility skills don't work underwater, and the only class elite they can use is Basilisk Venom, which is (at best) very mediocre for PvE. The Spear is an excellent defensive weapon, but it's not very powerful offensively. The Harpoon Gun is also defensive, but at least it has an offensive skill that does more damage than the basic attack...The Spear has limited AoE capability, and the Harpoon Gun has two skills that pierce foes in a line, and a weak AoE Poison, but none of those are very good in practice. (Lining up foes on land is hard enough, but almost impossible in the water.)

Stealing and Stealth

Stealing is the profession mechanic of the Thief. It has a 45 second cooldown (can be reduced with investment in Trickery) and Shadow Steps you right next to the enemy. Regardless, even when playing ranged, it's almost always worth using on recharge. If you're familiar with environmental weapons, you know how powerful those skills are. Well, Stealing is like that - except it gives you the weapon's best skill without replacing your weapon skills, and you can use it whenever you want. While some of these skills "only" deal some damage and apply conditions, others are extremely powerful effects that are difficult or impossible to replicate otherwise. For example, Tooth Stab applies Bleeding for a whole minute; Consume Ectoplasm applies every Boon in the game; and Throw Gunk applies many conditions in AoE in addition to creating the Ethereal Field. Finally, many Thief traits improve Stealing to cause other effects such as applying Poisoned or granting Boons to allies, so it ends up being a powerful and versatile tool. Learning to use Steal is crucial to mastering the Thief.

Stealth is not completely exclusive to the Thief, but it's pretty rare on any other class. Stealth makes you invisible to PvE foes and mostly invisible to PvP ones (there are a variety of tricks to detect a stealthed person, such as watching for damage numbers to pop up in empty air when using AoE). Stealth doesn't break when you take damage; it ends when you deal damage or at the end of the listed duration. Many Thief traits and abilities make use of Stealth.

Weapons (1 - 5)

The way the Thief works is that (except for Shortbow, which is two-handed) the main-hand weapon determines the first two skills; the off-hand weapon determines the fourth and fifth skills; and both weapons together determine the third skill. If you only have one weapon equipped in the main hand, then the third skill changes to a crappy filler that isn't worth using ever, so I'm not even going to bother mentioning them. The first skill changes if it's used from Stealth.

Shortbow

The Shortbow is a two-handed weapon that has 900 range for the Thief (longer for one skill). It has a good rate of fire and all of its skills are useful in multiple environments. Unfortunately, it largely relies on damage over time, so it's a slow weapon to kill with. Nevertheless, compared to all the other Thief weapons, the Shortbow is the only one that has some use in every situation (even out of combat).

It's worth noting that unlike some other ranged weapons (of other classes), the Shortbow can be shot in nearly a 180 degree radius. That is, if a target is directly to your left or right and you are facing forwards and strafing, you can still hit them, more or less. Compare this to an Elementalist using a Staff - most of their skills require you to be facing the target in a fairly narrow radius, even the non-projectile ones. This makes it much easier for a Thief to "run circles" around a target, aka "circle strafing".

Also, the Shortbow ground targeted skills can be fired "behind" you while running (easier if you disable the "ground target skills auto-cast at foe's location"). This is done by moving and aiming your shot at your current position or a bit behind. By the time the shot goes off, you'll have already moved past the location.

1. Trick Shot (Surprise Shot from Stealth). This attack deals mediocre damage and hits up to three targets if they're close enough together. If there are only two targets, it will hit the first, bounce to the second, and bounce back to the first, effectively dealing double damage. The arrows are homing; they never miss unless they're obstructed or the target dodges, etc. Finally, Trick Shot is a Projectile Finisher (20% chance). The upside is that it's a simple, unconditional skill with no frills. The downside is that it doesn't do anything special and it's actually really annoying in cramped areas where you only want to fight one foe at once (to "pull" them). Also, when there's only one foe, the damage is really poor. As for Surprise Shot - it's an okay skill, but definitely more PvP-oriented, since there aren't too many cases in PvE where such an unreliable Immobilize is worthwhile. (I say unreliable because it requires you to use some other skill to gain Stealth first, and you generally don't want to blow a skill just for that.)
2. Cluster Bomb (can be chained into Detonate Cluster). Unlike all the other Shortbow skills, this one has 1200 range. This is the only direct damage skill for Shortbow. At low levels this scales excellently and it is very powerful; later on it's only decent, but still stronger than Trick Shot. When Cluster Bomb is fired, it sends out a slow-moving arrow with a very high arc. Hitting the button again while the arrow is in flight will detonate the bomb into three smaller bombs in a triangular spread pattern; it takes practice to be able to make them land exactly where you want to. The large bomb generally does more damage, but in a really packed area, you can hit more foes with the small bombs sometimes. (AoE effects hit a maximum of five targets in Guild Wars 2, so the large bomb can hit 5 targets max. The small bombs are limited to 3 targets each, but if they all hit 3 targets that's 9 targets hit.) This skill also applies a negligible amount of Bleeding. Finally, Cluster Bomb is a Blast Finisher. The upside is that Cluster Bomb is your only means of dealing direct damage with a Shortbow, and at least at low levels it's quite strong; this is also, by far, the most common/easiest to use of all the Blast finisher skills. The downside is that it's extremely easy to dodge at long range because of the slow flight and high arc, and it can hit overhangs or even ceilings due to the high arc (while all your other attacks hit just fine), wasting the shot. When foes are right in your face, you can mash Cluster Bomb over and over for good damage, but that's generally not a good situation to be in for a Thief.
3. Disabling Shot. This skill causes the Thief to leap backwards, evading attacks, and simultaneously shoot an arrow at the foe that Cripples them for a short time. Combined with other defensive maneuvers, such as dodging, other snares, etc., this skill allows a Thief to indefinitely kite a single foe. Even against many foes, though, this is a useful skill - if your Endurance isn't high enough to dodge, but you have Initiative, you can use Disabling Shot to "dodge backwards". Unfortunately, the skill is somewhat buggy - sometimes the leap doesn't actually move you at all (although the evade works), even when a normal backwards roll does move you. On the plus side, Disabling Shot is a Projectile Finisher with a 100% chance, so it's useful to have when you absolutely need the combo effect to go off. Overall, a solid skill.
4. Choking Gas. This does no damage on its own, but creates a Poison Field at the targeted area and inflicts Poisoned each second that it's active. You can maintain Poisoned indefinitely against multiple foes just using this skill, and it gets even better when combo finishers are added in. The Shortbow conveniently has Physical Projectile (causes more Poisoned) and Blast (causes Weakness in AoE) finishers to use alongside Choking Gas. In a group setting, a lot of other players will combo with the field and cause even more Poisoned etc.
5. Infiltrator's Arrow. This ground-targeted skill fires a non-damaging arrow that Blinds foes in the (small) area of impact; the Thief then attempts to Shadow Step to that location. This skill is mostly useful for moving long distances very quickly, since other Shadow Step skills have cooldowns. Note that you cannot Shadow Step through obstructions, onto ledges, or otherwise use this skill to move somewhere that you couldn't get by directly walking; it may also randomly fail to move the full distance for no explainable reason. Still, this is one of the best abilities in the game for moving around, and it makes it very difficult to predict exactly where a Thief will be when using a Shortbow. Combined with Signet of Shadows, Infiltrator's Arrow gives the Thief the best mobility of any class in the game.

Overall grade: 9/10, highly recommend always having a Shortbow handy. It's useful in combat, and it's useful out of combat. It doesn't need any particular traits or utility skills to be good. True, the Shortbow usually doesn't do a lot of damage, so it's a defensive weapon; but, it excels at that job beautifully.

Sword

The Sword can only be wielded in the main hand (at least for the Thief). It hits fairly hard and the swings have AoE by default, but it's not as fast as a Dagger. The Sword is an interesting mix of offense and defense, although it is pretty strictly for use against general, weak enemies - being in melee range is suicidal for a Thief against many bosses, and in big AoE situations the Shortbow is superior. That being said, *if* you want to try to melee a boss, Sword is the best to use because it has skills to enable a quick escape if necessary.

1. Slice → Slash → Crippling Strike (Tactical Strike from Stealth). Deals good damage in swing AoE and causes Weakness and Crippled on the final hit. The Weakness doesn't last very long, unfortunately, so it's hard to maintain unless this is the only skill you use, or you spec for improved Condition Duration. Tactical Strike is handy if you happen to land it from behind, since 2 seconds of Dazed is relatively long in this game - especially for such an easy conditional. Most foes also conveniently face away from you after you enter Stealth. Unfortunately, it's a bit lackluster in PvE, where the big damage boosts of the Dagger or Pistol stealth skills are more useful overall.
2. Infiltrator's Strike (can be chained into Shadow Return). This Immobilizes the foe for one second, Shadow Steps you right next to them, and deals a bit of damage. Useful for chasing a fleeing foe and otherwise positioning yourself. Shadow Return cures a Condition when used, which is handy, although you burn a lot of Initiative if you use the chain purely for that. Then again, it's an unconditional Stun breaker, which is incredibly powerful for a skill that has essentially no cooldown.
3. Dual Wield skill:
   1. Dagger in offhand - Flanking Strike. This hits the foe to remove a Boon, attempts to Evade in a circle to get behind them, and then delivers a second powerful attack. On paper it is very good, but unfortunately it's buggy and unreliable in practice. The Evade doesn't always actually move you, and sometimes it moves you so far that you're actually out of melee range, forcing the Thief to manually walk back to the target. In addition, it's not an instant-cast skill; there's a slight delay between activating the skill and the Evade kicking in. Combined with the short Evade duration, this makes timing the skill very picky. Flanking Strike can be amazing if you're good with it, but compared to almost every other Thief skill it takes a lot of effort to make it work well.
   2. Pistol in offhand - Pistol Whip. After a short wind-up, this Stuns the foe for a very short time, and then attacks several times with the Sword. It does fantastic damage, but unfortunately there are two big problems. Firstly, the wind-up makes it difficult to time the Stun if you wanted to use it to interrupt something. Secondly, you're rooted in place while slashing with the Sword, which means that the enemy can simply move out of range after the Stun wears off, and you're also vulnerable to attack while using it (activating another non-signet skill/moving cancels the attack). Still, overall this is a great skill if the enemy is just standing still and you're not in danger of a strong counterattack. Note: Pistol Whip also sometimes randomly evades attacks, which mitigates the rooting somewhat.

Overall grade: 6/10 - 8/10, really depends on the situation. Infiltrator's Strike gives high mobility and stun breaker, which alone is pretty good, but the basic attack chain isn't that impressive (compared to Dagger). Stealth skill is more for PvP and pretty poor if conditional isn't met. Flanking Strike and Pistol Whip can both be very powerful in the right situations, but Flanking Strike is buggy/tricky and Pistol Whip is purely for offense. No particular synergy with Dagger offhand skills (see below), since Infiltrator's Strike is generally superior for catching fleeing foes, and Cloak and Dagger...eh. You're burning a lot of Initiative to get access to Tactical Strike on-demand. Works a bit better with Pistol offhand skills (see below): Headshot is a more reliable interrupt than Tactical Strike, and you're probably in melee range already so it should hit near-instantly, won't get obstructed, etc. Sword can't combo with Black Powder, but again, you're probably in melee range so enemies will be standing in the pulsing blind field.

Dagger

The Dagger hits really hard and really fast as a main-hand, and its off-hand skills aren't terrible either. The Dual Wield skills are, in my opinion, the best ones. Daggers don't offer any true defensive skills at all, though, so they're risky to use if counterattacks are possible. Also, the Dagger does not have inherent AoE on the swings, which is unfortunate but necessary for balance.

1. Double Strike → Wild Strike → Lotus Strike (Backstab from Stealth). This is a fantastic chain that hits the enemy four times in quick succession, refills some Endurance, and inflicts Poisoned. By far the most damaging basic attack a Thief has, and it combines well with all kinds of effects due to its speed - anything that triggers on attack/on hit. With the Lotus Poison minor trait, this chain also maintains Weakness indefinitely; not many classes can do that. Backstab is also exceptionally powerful when you land it from behind, dealing double damage; 14k critical hits aren't uncommon at level 80 with decent gear.
2. Heartseeker. Leap at the foe and deal more damage the less health they have. Not only is this useful for closing distances/moving around, it deals good damage at any percent - although naturally it's better when the opponent is weaker. Finally, Heartseeker is a Leap Finisher. At the moment, Heartseeker is bugged and has the unfortunate tendency to randomly miss targets, which can be frustrating...although like so many bugs in this game, it's random, so YMMV.
3. Dual Wield skill:
   1. Dagger in offhand - Leaping Death Blossom. Vault over your target, hitting that target and nearby targets three times, inflicting Bleeding with each strike, and also Evading attacks. This is an amazing skill that does so many things at once it's not even funny. It hits multiple targets in the area for heavy damage, it evades, and it moves you directly to the other side of the opponent (most times) - a unique movement. This is especially useful if you have the "Melee Attack Assist" option checked, which prevents you from running through enemies - sometimes the best way to evade is straight through the enemy. Did I mention it's a Whirl Finisher? The only downside to this skill is that it does funny things with the camera sometimes, and it does cost a lot of Initiative, so you really don't want to be disoriented after using it.
   2. Pistol in offhand - Shadow Shot. Fires a shot at the foe, inflicting Blindness. Then Shadow Step to them and attack with the Dagger. This is pretty purely for PvP as a gap closer; there's really no reason to use it if you're already at melee range unless you REALLY need a blind RIGHT NOW, since the damage is mediocre. (You have access to Black Powder, anyway - see below.) It's not even that great for pursuing a fleeing foe (better to Cripple/Immobilize them). I guess it's useful for positioning, but Leaping Death Blossom is so much more powerful. Shadow Shot is a Projectile Finisher.
4. Dancing Dagger. This is a neat skill that hits your foe and then bounces to up to three targets, causing decent damage and Crippling each one. Similar to Trick Shot, it can bounce between just two targets, hitting each one twice. This has just as much range as the Shortbow or Pistol, and it Cripples for 5 seconds, which is a good duration for a skill that has no real recharge and that much range. It's also a Projectile Finisher, which is neat because it means Dual Wielding Daggers gives three different Finishers - Leap, Whirl, and Projectile.
5. Cloak and Dagger. After a short delay, stab the foe, applying a little bit of Vulnerability for a short time, then vanish in Stealth for three seconds (assuming you hit something). A good skill, but it costs a lot of Initiative (6), so use wisely. Combos very well with Backstab if you can pull it off; during the wind-up, you can move, use Steal, etc. to get better positioning.

Overall grade: 9/10, only losing a perfect score due to having ~no defensive capabilities (on a fragile class already). All of the skills (except Shadow Shot) are unconditionally powerful in their own right. Dagger is weakest when paired with the Sword, and that's saying something because that grants Flanking Strike; buggy or not, it's a powerful skill. While I would not go so far as to say that a Thief should always utilize a Dagger, it remains a strong contender for most situations, and you should at least have a pair sitting in your inventory at all times.

Pistol

The Pistol is the other ranged weapon for Thieves. While it kills faster than the Shortbow, it has no AoE at all (Ricochet is just terrible), and so it's really only appropriate for single targets. The rate of fire is kind of slow, too. Pistol shots (except Unload) are not homing, but since bullets fly so fast in this game they might as well be (I have yet to dodge a bullet just by running from it). Similar to the Shortbow, the Pistol can be fired at almost a 180 degree angle, so it's great for "circle strafing" (although you will need to rely on other weapons/abilities for snares).

1. Vital Shot (Sneak Attack from Stealth). Shoot at the foe, dealing some damage and inflicting Bleeding. This actually inflicts more damage via Bleeding than the shots themselves, but it's still generally better than Trick Shot for single targets. It also means that you can singlehandedly maintain multiple stacks of Bleeding on a foe without even trying. Vital Shot is a Projectile Finisher with 20% chance. Sneak Attack fires off multiple rounds and also causes Bleeding; the damage is pretty good, not as high as a good Backstab, but comparable to Unload. Sneak Attack does have the distinction of being a Projectile Finisher with 100% chance, though.
2. Body Shot. Shoot the foe for some damage, and also influct a moderate amount of Vulnerability for a moderate amount of time. Almost never worth using in any situation; when you're alone, the Initiative is better spent on direct damage, and in a group, other classes have far superior ways to cause, or even stack and maintain, Vulnerability anyway. Body Shot is a Projectile Finisher.
3. Dual Wield skill:
   1. Dagger in offhand - Shadow Strike. This is the more defensive option. Stab the foe with your Dagger, then Shadow Step directly backwards and shoot them with your Pistol. Combined with having Dancing Dagger available, this allows a Thief to kite away from a foe while continually shooting them; just use this whenever they get close.
   2. Pistol in offhand - Unload. This is the more offensive option. You shoot the foe rapidly with 8 attacks, and you can continue moving while shooting (although it ends prematurely if you Dodge). The damage is not bad, but it's a bit of a plain skill since it lacks any other functionality. Unload is a Projectile Finisher with a 20% chance, which means it's pretty likely to trigger at least once.
4. Headshot. Shoot your foe for low damage, causing Dazed for 1/4 second. This is basically a fast interrupt and nothing else, although it's a good one at that. Headshot is a Projectile Finisher.
5. Black Powder. This is a unique skill because it combos with itself. Create a Smoke Field at your location, blinding foes around you with each pulse, then fire a shot at your target (comboing through the Smoke Field and blinding the foe). Black Powder is a Projectile Finisher, although that is functionally meaningless because it will (almost?) always combo with its own Smoke Field. While Black Powder does minimal damage, it is a powerful defensive skill well worth taking in many situations. Enemies that enter the Smoke Field will gain aggro on you, even though it does no damage, which can be problematic in PvE.

Overall grade: 7/10, even against a single target. Pistol lacks the mobility skills of other weapons, and the damage isn't really enough to make up for it. It's also pretty useless outside of combat, unlike the other weapons. The problem with Unload is that it is purely raw damage, while Vital Shot is mostly Bleeding damage; you can't have Power, Precision, Crit Damage, Condition Damage, and Condition Duration all at the same time, so one or the other skill becomes useless. Sneak Attack is a much better burst option, since that also relies mostly on Bleeding...but then Unload becomes pointless and you have no burst outside of Stealth, and outside of Pistol/Dagger you'd need to blow a heal/utility skill to Stealth. No gap closer or snare is also a big issue (Shadow Shot isn't particularly good at either of these). Headshot is questionable for PvE, since a lot of bosses are (semi) immune to interrupts anyway; Black Powder is pretty good, but it is most useful when enemies are sitting right in your face, and Smoke Screen is a perfectly viable alternative for that sort of situation.

Spear (underwater)

The Spear is a highly defensive weapon; Thieves don't get any powerful offensive maneuvers with it, though, and it has no combo fields or finishers at all. Fortunately, there are only two underwater weapon types, so you don't have to decide which ones to use. Put a Spear in one slot and a Harpoon Gun in the other.

1. Stab → Jab → Poison Tip Strike (Deadly Strike from Stealth). Meh. A boring chain that doesn't deal that much damage, and the condition durations are short. The Bleeding from Deadly Strike is decent, but getting Stealth underwater is harder than on land. Has swing AoE, max 3 targets.
2. Flanking Strike. Evade around your foe and then stab them for decent damage, inflicting a little bit of Vulnerability for a moderate amount of time. It's basically like Body Shot - not worth using unless no one else is influcting Vulnerability. Only time I'd use this instead of Nine Tailed Strike is if I was trying to Evade more than one thing at once, and the only time I'd use this instead of Shadow Assault is if I didn't have enough Initiative. This has the same problem as Flanking Strike of sometimes not moving correctly or putting the Thief outside of melee range, too...
3. Nine Tailed Strike (chains into Break Stance). This is an extremely cheap skill that costs 3 Initiative. If you end it early by using Break Stance, you regain 3 Initiative, and you'll regain it naturally if it's allowed to expire on its own too. Block one attack and then counter with a flurry of strikes; max 3 targets AoE. Against a single foe, this skill can singlehandedly allow you to win a fight. However, it is still countered by the fact that it only blocks once - any attack that hits multiple times, or an enemy that doesn't get shaken by your attacks and hits immediately again anyway, will overcome this defense. Still, a great skill, and probably the best damage you can do with a Spear overall. You can move while the stance is up.
4. Tow Line. Shoot a tow line at the target, dealing minor damage and pulling you to them. This would be a good skill, except it stuns you for a second or two after use, while the enemy is not stunned at all. Therefore it leaves you extremely vulnerable, and that makes it pretty poor in my book. Only really useful as an emergency interrupt, since any fleeing enemy will just continue swimming away from you after you're stunned.
5. Shadow Assault. Evade attacks and strike your enemy three times for decent damage. This is useful if you're having trouble timing a Block/Dodge with Flanking Strike or Nine Tailed Strike, or when there are multiple foes attacking at once. Also works well against enemies that hit multiple times in a row - the Evade lasts about three seconds, longer than almost all underwater attacks. It does cost a lot of Initiative; on the other hand, you'll regain some while the skill is channeling, so it can be used 4-5 times in a row if needed.

Harpoon Gun (underwater)

The Harpoon Gun is also a defensive weapon. The Harpoon Gun has 1200 range, which is the maximum for a ranged weapon without upgrades.

1. Piercing Shot (The Ripper from Stealth). A piercing shot that hits your foe, everything in front of it, and everything behind it in a line. Low damage, but inflicts Bleeding. Projectile Finisher. The Ripper does the same amount of damage, but about five times as much via Bleeding. It only has a 20% Projectile Finisher though.
2. Deluge. Fires four shots in rapid succession for decent damage. This is basically the underwater equivalent of Unload. 20% Projectile Finisher.
3. Escape. After a brief delay, shoot a shot at your foe for slightly improved damage, leave a cloud of poison at your location for a brief time, and then get blown backwards fairly far. The Poisoned duration is only one second, which is completely negligible, and the damage is not as good as Deluge. This skill is mostly used for what it's named - escaping. Combos well with Withdraw to really cover distance. Projectile Finisher.
4. Disabling Shot. After a brief delay, shoots a shot at the foe for decent damage and inflicts Crippled for 5 seconds. I wish it didn't have the delay, but it's an okay skill. Disabling Shot is a Projectile Finisher.
5. Ink Shot (chains to Smoke Trail). A piercing shot that damages and blinds all foes in a line. When it reaches the end of its range, hits an obstruction, or you use Smoke Trail, you will Shadow Step to the end location. If you know how to use this skill, it's fantastic for mobility and such, and blinding multiple foes (while difficult) is neat. I find it hard to keep track of the shot's location, though, and often end up somewhere totally unexpected at the wrong time...in PvP this is okay because your enemies might also lose track of you, but PvE foes don't have any problems immediately re-targeting.

Healing Skills (6)

All of the Thief's healing skills are useful in their own situations; no one skill is absolutely better than the others (which is decidedly untrue for other professions).

• Hide in Shadows. Thieves start with this skill. After a short cast, vanish in Stealth, gain Regeneration, and heal yourself for a strong amount. Cures Burning, Poison, and Bleeding. This is a multi-purpose skill and pretty good overall. The heal is strong, and removing the three damage over time conditions will save your life many times. Stealth also opens up opportunities for all sorts of strategies and combinations, both offensive and defensive. The major downsides to this skill are the casting time and the recharge of 30 seconds - if for whatever reason you fail to cast Hide in Shadows, you're basically dead, and if conditions are reapplied quickly (e.g. fighting Risen, Necromancers, etc) you're in trouble. Also, it doesn't break Chilled, Immobilized, or Crippled, forcing you to use some other skill for that. (Especially in PvP, not being able to break snares is a huge disadvantage - but there are plenty of PvE foes that can make your life hell with them as well.) Hide in Shadows is more useful for the later parts of the PvE game, where the damage over time conditions are more common and deal more damage.
• Withdraw. Unlocked for one Skill Point, and definitely worth getting as soon as possible. Withdraw heals for about 70% of Hide in Shadows, but it has only half the recharge time. It causes you to dodge backwards, evading attacks and curing Chilled, Immobilized, and Crippled. The great thing about Withdraw is that it does more (direct) healing over time than Hide in Shadows, it breaks snares, and it casts instantly so it's very difficult (if not impossible) to interrupt. It's also basically a third roll, and since the cooldown is so short, it's perfectly acceptable to use it purely for the evade. The major downside to Withdraw is that it doesn't cure those damage over time Conditions; Poisoned especially is dangerous since it decreases the already-lower healing. Thieves don't have good options for removing those conditions, since the available skills have lengthly recharge, are mediocre, and/or they, of course, take up another skill slot that could be better used for something else. Withdraw is more useful in the earlier parts of the PvE game, where the damage over time conditions are less common and don't deal much damage. However, Withdraw has an interesting property when used underwater - it blows your character backwards REALLY FAR, often completely out of the water in shallower areas. While this can be annoying, it's also fantastic for defense, since very few foes can catch up to you, especially if you also have the Harpoon Gun equipped for Escape.
• Signet of Malice. Unlocked for three Skill Points; optional but good. This passively heals for a little bit every time you attack. The active effect heals for a bit less than Withdraw. The cooldowns are the same, but Signet of Malice has a casting time. Signet of Malice is a good skill if you're taking smaller packets of damage, and it can kind of counteract the effects of one damage over time condition (but not more than one at once). It also combos really well with Dagger Storm, granting basically a full heal and semi-invulnerability. The major downsides of Signet of Malice are that it doesn't cure any conditions at all, and it doesn't do the roll that Withdraw does - it only heals. Those extra utility functions are very valuable, and I find myself missing them all the time when I use Signet of Malice. On the other hand, there are three Thief traits that interact with signets, so...
• Prayer to Dwayna. This is for Humans only. Unlocked for three Skill Points; pass. Has the same recharge as Hide in Shadows, and casts instantly (I think? don't actually remember) but heals for slightly more. Other than that it doesn't do anything interesting. I don't really see the point of this skill, and it doesn't even work underwater.

Slot Skills (7 - 10)

The Thief's utility skills are a varied lot, but the one thing they have in common is that most of them work equally well no matter what weapons or traits one is using. I'm organizing these by the order they are available in-game via the tier system.

Tier 1 - one Skill Point each

• Blinding Powder. Blind all foes around you and grant Stealth to yourself and allies near you. Has a really long recharge at a minute, and can't be used underwater - for those reasons, not recommended early on. It's a good panic button in the later game or for PvP, when you have traits that make Stealth do other things.
• Assassin's Signet. Passively grants increased Power. Active effect causes your next attack to deal 150% damage, but the recharge is 45 seconds, so really only worth using for Backstab. At least it works underwater.
• Infiltrator's Signet. Passively regenerate one extra Initiative every ten seconds. This is approximately a 16.7% increase in Initiative regeneration. The active effect is to Shadow Step to your foe and break Stun, on a 30 second cooldown and 900 range. This is the poor man's version of Shadowstep the skill - it has 300 less range, doesn't cure Conditions, has to target a foe to move, and doesn't chain to Shadow Return. On the plus side, it recharges 20 seconds faster and the passive is passable, if you'll excuse the pun. Optional; there's no situation in the early game where this is particularly useful, but at least it works underwater.
• Tripwire. Set a Trap that knocks down, Cripples, and slightly damages foes when triggered. The trap is set in a long rectangular formation. The knockdown lasts a full three seconds, which is really long - plenty of time to run away from an enemy if need be, or to finish them off quickly. The recharge is also 30 seconds, which isn't bad. However, note that only one Tripwire can be active at a time, and it disappears if you move too far away. Traps also can't be used underwater; moreover, they behave oddly, and sometimes they flat-out just don't work, for reasons I do not understand. It might be that certain foes are immune to traps, like flying ones; but that's weird, because other ground-based effects work on them. Anyway, this is a good skill if you can get it to work reliably.
• Roll for Initiative. Evade backwards (similar to Withdraw), regain 6 Initiative, break Stun, and cure Chilled, Immobilize, and Cripple. This is a great defensive skill, works underwater, and can also be used to add more damage to burst if necessary. However, the recharge is really long at 60 seconds, so if you're going to use this, make sure it counts. You're better off buying Withdraw early on.
• Scorpion Wire. Throw out a Scorpion Wire at 900 range, causing minor damage and pulling your foe to you. The projectile moves a bit slowly and it can be dodged/obstructed/etc, though. Unlike Tow Line, this doesn't stun your character, and this can also be used underwater so it completely replaces that skill in such a case. It is also a Projectile Finisher, and as a pull, functions as an interrupt. Finally, the recharge is 30 seconds, very reasonable. A great skill and highly recommended.
• Spider Venom. Coats your weapon in a Venom that has 5 charges. Each attack depletes a charge, even if the attack is Blocked, Evaded, Misses, is Obstructed, etc. Spider Venom's effect is to Poison the foe for 6 seconds per hit, for a total of 30 seconds over all five charges. It's decent, but Choking Gas from the Shortbow and Lotus Strike from the main hand Dagger already inflict enough Poison to stack infinitely. Poison also stacks in duration, not intensity; therefore, if a foe isn't actually going to be alive for infinite time, adding more duration isn't particularly helpful. The main usage of Spider Venom is to add Poison to the Pistol or Sword; even then, with a 45 second recharge, it's not maintainable unless you trait for it. Not recommended, but at least it works underwater.
• Prayer to Kormir. Human only. Pray to Kormir, curing three Conditions on yourself. 40 second recharge. This is a decent skill; the recharge is a bit long for my likes, but it can be a real lifesaver when there are lots of conditions flying around. Unfortunately it doesn't work underwater, and Shadowstep does the same thing on 10 seconds more recharge, but also has other properties, including being able to be used underwater. Therefore, this is a bad skill for Thieves.

Tier 2 - 3 Skill Points each

• Signet of Agility. Passively grants increased Precision, which improves your Critical hit chance. Active effect: Fully restore Endurance and cure one condition on yourself and nearby allies on a 30 second cooldown. This is mediocre, but can be good with a proper setup - properly timed, it will allow for four consecutive rolls in a row, and combining it with Withdraw and/or Roll for Initiative makes even more. The Condition removal is just a bonus, and it's the only way for Thieves to remove Conditions on allies. The problem with Precision, though, is that it becomes redundant to stack it past a certain point; I haven't done the math, so I don't know the breakpoints, but at a certain chance to crit, you will be better off investing in Power for raw damage or Critical Damage to make those Critical Hits more effective. Still, a decent skill, and works underwater.
• Needle Trap. Set a rectangular Trap that does minor damage, Immobilizes for 3 seconds, and Poisons for decent duration when triggered. I don't like this as much as Tripwire, because Knockdown is a stronger debilitation than Immobilize. The Poison is also superfluous, since Thieves have better ways to cause that condition. You can only have one Needle Trap out at once, it disappears if you move too far away, and it can't be used underwater. Overall, not recommended - take Tripwire instead if you want to use Traps. Only time I'd take this is if I knew I was going to fight a foe immune to Knockdown, but even then...meh. Oh, and similar to Tripwire, this Trap randomly fails at odd times.
• Shadow Trap. This trap doesn't deal any damage. Instead, when it is triggered, you Stealth for 5 seconds and Shadow Step to its location. The maximum range you can move away from the Trap is about 2800, which is fairly long - however, just remember that you can't Shadow Step up cliffs, through walls, etc. This is mostly useful in PvP to set up ambushes for unsuspecting players; I can't think of any use for this in regular PvE play. The recharge is only 30 seconds, so I guess you could use it purely to enter Stealth mid-combat, but it seems like a waste of a skill slot just for that. Especially since, being a Trap, it's not usable underwater.
• Caltrops. A fantastic skill, one of the best utilities in the game. After a short cast, you drop a ton of Caltrops on the ground at your location in a huge radius. You can move while casting. The Caltrops persist for 14 seconds, and EACH SECOND that they are active, they (re)apply 3 seconds of Bleeding and 10 seconds of Crippled to any foe that touches them. That means you can keep multiple foes snared for up to 24 seconds, without +condition duration, just with this one skill, and during that time they will also take a ton of damage from Bleeding. Great to use while running away, and also great to drop right in the middle of combat on top of foes. Note that even flying foes are affected by Caltrops. The only problem with this skill is that it doesn't work underwater. Highly, highly recommended to purchase as soon as possible.
• Haste. Break Stun and gain Quickness for 4 seconds, but lose all Endurance, and it won't regenerate while Haste is active. This is deadly for a Thief, since dodging is one of our primary defenses; therefore, this is a PvP-oriented skill used for extreme burst damage. Quickness causes all actions to happen ~twice as fast. The recharge on this is really long, at 60 seconds, but it should be that way. A niche skill that you won't use most of the time; buy it later.
• Ice Drake Venom. Apply three charges of Ice Drake Venom to your weapon, causing Chilled on the next three hits for one second each. Chilled is a powerful condition, but the totally pitiful duration makes this skill a complete waste almost all the time. The Shortbow and offhand Dagger can already cause Cripple easily, anyway.
• Skale Venom. Apply three charges of Skale Venom to your weapon, causing 1 stack of Vulnerability for 5 seconds and 5 seconds of Weakness for each hit. The Vulnerability is quite negligible - because it stacks in intensity rather than duration, you will be dealing 3% more damage for 5 seconds total. That's less than a single Body Shot. The Weakness is okay, but without traits you're only going to be keeping it up 1/3 of the time; Lotus Poison is a better way to do Weakness, anyway.

Tier 3 - 6 Skill Points each

• Shadow Refuge. Cast a Shadow Refuge at the target location, range 600, huge radius. It persists for 4 seconds, and each second it pulses, granting allies 3 seconds of Stealth and healing them for about 30% of a Withdraw. The Stealth stacks up to 12 seconds of duration if you sit still for all four pulses. This also creates a Dark Field to combo with. Although the recharge is long at 60 seconds, this is a great skill to have at all times - it's energency healing, and the Stealth lasts long enough that any enemy will stop paying attention to you and go back to where it was, giving you time for other skills to recharge and possibly even letting you leave combat so you can use a Waypoint. It works well in PvP, too - bad players don't understand this skill, so they assume you just vanished mysteriously. One tactic is to cast Shadow Refuge on top of a downed or defeated ally before starting to revive them - it's good cover and prevents most kinds of interruption. Unfortunately doesn't work underwater.
• Shadowstep. A ground targeted skill with range 1200. Break Stun and Shadowstep to the target location. Chains into Shadow Return, which returns you to your starting location and cures three Conditions. This skill has a long recharge at 50 seconds, but it can really save your life if you know how to use it well. 1200 is far enough that most things will stop chasing you entirely if you run away, even without a speed buff; and you can just use it during battle if you want to, simply to cure Conditions. It also works underwater. This is a good skill to buy early; while it's simple enough to use immediately, truly mastering its usage will take time.
• Smoke Screen. This drops a Smoke Field at your location, persisting for 7 seconds, although it is shaped like a Thief Trap (rectangle). While it is active, it Blocks incoming projectiles, and Blinds foes that touch it for 1 second every second (pulsing). The recharge is only 30 seconds, too. Unfortunately it doesn't work underwater. Not a bad skill, but if you're using off-hand Pistol then Smoke Powder is kind of redundant with this. Note that enemies touching the field gain aggro, despite the fact that Smoke Screen deals no damage; this can cause unfortunate accidents in PvE.
• Signet of Shadows. Passively grants a 25% speed boost (does not stack with Swiftness or other speed-enhancing effects). Active effect is to Blind foes near your target for 5 seconds, 30 second recharge. This is one of the best utility skills in the game and I would recommend buying it as soon as possible, and never taking it off your bar. 25% speed boost is enough to outrun most foes in PvE, and during battle it helps you get around quicker as well. The active effect is a panic button if you really really need Blind immediately.
• Ambush. Set a trap that spawns a Thief NPC to fight by your side for 20 seconds when triggered. The Thief spawns at your location, not at the trap. This is the poor man's Thieves Guild. Since I use that elite a lot, I can testify to how useful the Thief allies are. They deal good damage (considering that they're NPCs), have decent health and armor, and apply a variety of status conditions. The problem is that, like all other NPCs, they have poor AI and will mindlessly attack any hostiles around you, which can lead to unnecessary fights. They also have the tendency to just stand in AoE effects and get hammered, and they rarely Dodge to avoid anything. Still, they are a good distraction, if nothing else, and the recharge is 35 seconds so you can potentially have an ally with you about 57% of the time. This is a good skill overall; it's a shame that it can't be used underwater.
• Devourer Venom. Applies two charges of Devourer Venom to your weapon, causing your next two attacks to Immobilize for 2 seconds. This is mostly a PvP-oriented skill; in PvE, the recharge of 45 seconds is too long to be of use most places, and you have better snares available already.

Elite Skills, Tier 1 - 10 Skill Points each

• Basilisk Venom. Applies a single charge of Basilisk Venom to your weapon, causing your next attack to petrify your target. This is hilariously bad for PvE - the petrification only lasts 1 second, while the recharge of this skill is 45 seconds. Even in PvP, there are other ways to root the target for a spike, such as Infiltrator's Strike. Also, unlike all other venoms, this one has a cast time - so it can be interrupted, and it isn't ready immediately when you need it. Petrification does the same thing as Stun, except it can't be broken. The only useful thing about it is that it can be used underwater. The only reason to buy this is to unlock the next tier of elite skills, but you may as well invest in a racial elite instead.
• Thieves Guild. This has a really long cooldown, at 3 minutes, but it's worth it. After a two-second casting time (during which you can move), two Thief NPCs are summoned to your location to fight by your side for 30 seconds. One of them Dual Wields Daggers and the other Dual Wields Pistols. I haven't been able to check exactly what skills they use, but I know at the very least that the Daggers one causes Poison (and maybe other conditions), and the Pistols one uses Unload and Black Powder (maybe Blinding Powder or Smoke Screen instead; it's AoE blind anyway). They deal a surprising amount of damage, have decent health and armor, and make for good distractions. As mentioned with Ambush, though, they have dumb AI...and there are plenty of situations where they're a total waste of time because they get themselves killed too easily, and then you're out an elite for three minutes. Thieves Guild is a good elite to use when facing only a few foes (for example, Skill Challenges), or when your main goal is to survive/run away. Thieves Guild cannot be cast underwater, but if you cast it outside the water and then dive in, the Thieves will follow. Also, Thieves Guild does not break Stealth, so casting it while e.g. inside Shadow Refuge is a good way to surprise people in PvP.
• Avatar of Melandru. Human only. Transform into an Oakheart for 20 seconds, and gain 20 seconds of Stability. Your first five skills are replaced; while transformed, you can deal good damage, remove Conditions from, grant Protection to, and/or heal yourself and allies in the area, and Immobilize all nearby foes with roots. This is a decent elite, but the duration is short, and you'll only be able to get off the skills once or twice before it ends (except the damage skill, which has no recharge). The recharge is long, at 180 seconds. It can't be used underwater. Still better than Basilisk Venom, though, and Stability is powerful.
• Reaper of Grenth. Human only. For 15 seconds, you automatically Chill and Poison any enemy that comes near you. This is pretty mediocre, especially with a long recharge of 180 seconds and being unable to use it underwater. AoE Poison is really easy to inflict with a Shortbow already. Still better than Basilisk Venom, though...and I guess 15 seconds of AoE Chill could be useful sometimes.
• Summon Mistfire Wolf. Rather than costing Skill Points, this is only available to Digital Deluxe or Collector's Edition purchasers - there is no other way to get this skill. This summons a Mistfire Wolf to fight at your side for 30 seconds. The recharge is REALLY LONG at 240 seconds, and it can't be used underwater. What's worse, from asking people who have it, I've heard that the Mistfire Wolf tends to needlessly attack things, isn't very powerful or tankish, and has dumb AI. Therefore, if you're considering upgrading purely for this skill, I'd say you're not getting your money's worth. At least it causes Chilled and Burning, but...blah.

Elite skills, Tier 2 - 30 Skill Points each

• Dagger Storm. For 8 seconds, you spin around, throwing Daggers in random directions. Each Dagger deals damage, Cripples for 2 seconds, Bleeds for a bit of damage, and also bounces to other targets. You gain Stability while this skill is active, reflect projectiles, and you can move while spinning - Dodging cancels it early. This is also a Whirl Finisher. Dagger Storm has half the recharge of Thieves Guild, at 90 seconds, and it's a superior skill when facing many foes. Because the Daggers bounce, this skill can actually cause a massive amount of damage, as long as you get lucky and a suitable number of Daggers find their mark - using this skill alone, assuming some luck and enough foes, will kill everything in the area. The major downside is that non-projectile enemies can still run up and hit you, and this skill has a tendency to piss off foes very quickly in PvE (drawing tons of aggro). If you don't have Signet of Malice equipped, be prepared to heal immediately after using Dagger Storm, or pray that someone else manages to keep enemies distracted. Still, this is a great elite, and more useful for general play because of the shorter recharge. Unfortunately, it can't be used underwater.
• Hounds of Balthazar. This is basically the same as Summon Mistfire Wolf, except it summons two dogs instead of one. They're not any smarter, although they fight somewhat better. Since this skill has a 240 second recharge, can't be used underwater, and the hounds only last 30 seconds, I have to say it's pretty garbage. Don't bother purchasing this; get Dagger Storm instead, and use Thieves Guild if you need allies.

Downed and Drowning

The Thief has annoying skills for these situations, but they aren't likely to Rally you, so in solo situations they're kind of bad.

Downed:

1. Trail of Knives (Venomous Knife from Stealth). Throw a bouncing knife that cripples foes. Pretty weak, but if you're lucky it might bounce to a weak target (or a critter) and Rally you that way. Venomous Knife doesn't bounce, but it does Bleeding and Poison, so it's more likely to kill a single target.
2. Shadow Escape. Teleport (not Shadowstep, so it goes ~anywhere) to the target location. The range isn't long enough to get out of aggro usually, but in PvP this is used at the last second to deny people from Finishing you. Can also be used to get out of AoE.
3. Smoke Bomb. Doesn't blind, just stealths you for 2 seconds and leaves a distracting visual. Going Stealth prevents enemies from Finishing you in PvP.
4. Bandage. Everyone gets this while Downed. Channel to heal yourself.

Drowning:

1. Diving Knife. Throw a knife at the foe to bleed them. Does most of its damage via bleeding; no extra ability from Stealth.
2. Cheap Shot. Knock back the foe with a kick. Short recharge, at 5 seconds, so annoying.
3. Vanish in the Deep. Stealth for 2 seconds.
4. Bandage. See above.

Traits

Please read the Trait page for an overview of how the system works.

Deadly Arts

Deadly Arts adds 10 Power and 1% Condition Duration for every point spent. These passive bonses alone make it an excellent choice.

• Adept Minor Trait - Serpent's Touch. Apply Poison for 10 seconds upon Stealing. On its own this isn't terribly impressive, but it combos well with many other things.
• Master Minor Trait - Lotus Poison. Apply Weakness for 3 seconds every time you apply Poison. This is an AMAZING trait and I can't recommend it enough. The Thief has tons of ways to apply Poison, and with this trait it's very easy to permanently maintain Weakness as well.
• Grandmaster Minor Trait - Exposed Weakness. Deal 10% more damage if your target has a Condition. This is such an easy condition to meet if you're a Thief - you're all but guaranteed to always have some Condition or other active.

Deadly Arts Adept Major Traits

• Back Fighting - +50% damage while Downed. I can see how this might be useful, but I prefer to avoid being Downed in the first place.
• Corrosive Traps - Traps apply 5 stacks of Vulnerability for 5 seconds when triggered. Quite mediocre, since Traps have too long of a cooldown in comparison to this duration, and Body Shot works just as well (meaning to say, it's useless).
• Mug - Deal damage when Stealing. Hits surprisingly hard, like up to 5k crits at level 80 (not sure if stats affect it). Definitely the best pick for this category.
• Venomous Strength - Gain 2 stacks of Might for 20 seconds after applying a Venom. I'd like this more if Venoms had shorter recharges or were generally more useful skills anyway. 20 seconds is still a good duration, but it's only two stacks, which is negligible...really only worthwhile with Venomous Aura (see below).
• Potent Poison - Increases Poison duration by 33%. Not that useful, since this trait line already improves condition duration, and Poison stacks in duration rather than intensity. It's easy for Thieves to maintain Poison anyway.
• Sundering Strikes - 40% chance to cause one stack of Vulnerability for 5 seconds on a Critical Hit, 1 second cooldown. Garbage.

Deadly Arts Master Major Traits

• Improvisation - Stealing recharges all skills of one type (venoms, signets, traps, tricks, or deceptions). This would be a good skill, except that it chooses the skill type randomly, and doesn't even care what type of skills are already on your bar. Because of this, I consider it to be too random to be useful. It can pay off big if you're super lucky, or it can be a total waste of a trait.
• Quick Venoms - Venom skills recharge 20% faster. Not very good unless you're using Venomous Aura.
• Dagger Training - Dagger damage is increased by 5%. A quality choice, being unconditional, although obviously does nothing if you're not using Daggers.
• Combined Training - Dual Wield skills do 5% more damage. This is decent, but it doesn't affect Shortbow at all, and Shadow Shot and Shadow Strike hardly benefit since their damage is so low already. Mainly used to add power to Pistol Whip or Unload.

Deadly Arts Grandmaster Major Traits

• Panic Strike - When you strike a foe with less than 50% health, you cause immobilize for 4 seconds. 60-second cooldown. This is a PvP skill, but a good one...assuming it triggers at the right time.
• Residual Venom - Venoms apply one extra charge. Not worth a Grandmaster trait outside of Venomous Aura.

Critical Strikes

Critical Strikes adds 10 Precision and +1% Critical Damage for each point. These are also excellent passive bonuses, complementing each other, and make the trait line good by themselves.

• Adept Minor Trait - Keen Observer. +5% Critical Hit chance while health is over 90%. This is useful, but in practice (especially in solo situations) the condition is difficult to meet consistently.
• Master Minor Trait - Opportunist. Critical Hits have a 20% chance to restore 1 Initiative, 1-second cooldown. This is okay, but it's naturally unreliable. It may trigger a bunch of times in a row, or it may not trigger at all for hours.
• Grandmaster Minor Trait - First Strikes. +10% damage when Initiative is over 6. This is okay, but becomes much better when combined with the Trickery Master Minor Trait, which increases total Initiative by 3 (up to 15).

Critical Strikes Adept Major Traits

• Furious Retaliation. Gain Fury for 10 seconds when your target reaches 50% health. 45-second cooldown. This is decent, although the recharge is kind of long for PvE usage.
• Signets of Power. Using a Signet grants 5 stacks of Might that last 5 seconds. Also decent; 5 stacks is starting to be useful, but 5 seconds is a short time. Used for spike builds with Assassin's Signet.
• Side Strike. +7% chance to crit when hitting a foe from behind or from the side. This isn't too useful in solo play because most things face you head-on, but it's good in group settings and PvP (and wonderful with Backstab).
• Concealed Defeat. Create a Smoke Screen when Downed. 10-second cooldown. This is annoying because things have to get in melee range to Finish you anyway, and for PvE it's 7 seconds of safety against most things. Probably the best PvE choice in this category.
• Pistol Mastery. +5% damage with Pistols. It's too bad Pistol isn't a better weapon to justify taking this.
• Practiced Tolerance. 5% of Precision is converted into Vitality. This is an interesting choice, granting some bonus health - it lets you boost your defenses while boosting your offenses. Probably the most universally useful choice, although since Thief has low base health anyway it's not ideal.

Critical Strikes Master Major Traits

• Ankle Shots. Critical Hits with a Pistol have a 60% chance to Cripple foes for 3 seconds. 10-second cooldown. Not terribly reliable - randomly Crippling a foe is inferior to having an on-demand Cripple, even if it involves using a skill or swapping weapons. Still, Pistol doesn't have any other snares.
• Signet Use. Gain 2 Initiative when activating a Signet. Signets recharge 20% faster. Not bad, especially if Signet of Malice is your heal.
• Combo Critical Chance. Dual Wield skills have +5% chance to crit. Most useful for Pistol Whip and Unload.
• Critical Haste. 10% chance to gain 2 seconds of Quickness on a Critical Hit. 30-second cooldown. Unreliable, but can be amazing if it triggers at the right time.

Critical Strikes Grandmaster Major Traits

• Executioner. Deal +20% damage when your target is under 50% health. Very powerful, and no cooldown either.
• Hidden Killer. 100% chance to crit from Stealth. Works best with Backstab. Unfortunately, bugged right now and it actually isn't 100% critical chance; probably should take Executioner until it's fixed.

Shadow Arts

Shadow Arts adds +10 Toughness and +10 Healing Power for each point spent. It's a good line to increase survivability, but Thieves aren't really designed to be taking hits in the first place, and they have almost no capability to heal people other than themselves; I feel this trait line isn't particularly useful, at least for the inherent bonuses.

• Adept Minor Trait - Last Refuge. Use Blinding Powder when your health reaches 25%. 90-second cooldown. I don't find this to be terribly useful. It'll grant a second or two of reprive from attacks, maybe... damage that was already en route to you will still go through, so meh.
• Master Minor Trait - Meld with Shadows. Stealth skills last 1 second longer. This isn't very useful unless you have multiple ways to Stealth, so that it adds up.
• Grandmaster Minor Trait - Hidden Assassin. Gain Might for 15 seconds on Stealth. It's 2 stacks, but has no cooldown, so if you have multiple ways of Stealthing it's possible to stack considerable Might this way.

Shadow Arts Adept Major Traits

• Master of Deception. Deceptions recharge 20% faster. The relevant skills are Blinding Powder, Shadowstep, Shadow Refuge, and Smoke Screen. These skills all have long-ish recharge, so a decent choice.
• Slowed Pulse. Gain 10 stacks of Regeneration when you have 5 or more stacks of Bleeding. 30 second cooldown. This is interesting, since it negates the Bleeding (up to a certain point) and persists even if the Bleeding is removed...say, via Hide in Shadows. Unfortunately, there's no way to self-inflict Bleeding as a Thief.
• Shadow Protector. When you Stealth an ally, including yourself, they gain Regeneration for 5 seconds. This is a nice additional heal, especially if you have multiple skills granting Stealth on your bar.
• Shadow's Embrace. Remove a condition every 3 seconds while in Stealth (also almost immediately upon entering Stealth). Almost all Stealth skills conveniently last for 3 or more seconds, so this can be a very powerful skill if you have many ways to apply Stealth.
• Infusion of Shadow. Gain 2 Initiative when using a skill that Stealths you. As with others, useful with multiple Stealths.
• Cloaked in Shadow. Going Stealth Blinds nearby foes. Can get annoying really quickly, although redundant for Blinding Powder.

Shadow Arts Master Major Traits

• Power Shots. Shortbow and Harpoon Gun damage increased by 5%. I don't like this, since the Shortbow doesn't deal great damage anyway. It's a little better with the Harpoon Gun, as that has Deluge, but meh.
• Hidden Thief. Stealing grants you 2 seconds of Stealth. One problem with Thieves is that it's somehat silly to Steal when using a Shortbow or Pistol main hand (putting you in melee range), or against dangerous foes like Champions. This largely solves that issue.
• Leeching Venoms. Steal health when triggering a Venom. Can only occur once per strike. Not worth it outside of Venomous Aura.
• Patience. Regain Initiative faster while in Stealth. It's approximately TWICE as fast as normal regen, which is wonderful.

Shadow Arts Grandmaster Major Traits

• Shadow's Rejuvenation. Regenerate health while in Stealth. This combines well with Shadow Protector, turning all Stealth skills into decent heal-over-time (this doesn't apply the Regeneration boon, but it stacks with that effect). Of course, you have to stay in the Stealth to get the effect, which is not always desirable.
• Venomous Aura. When you use a Venom skill, you apply the effects to all nearby allies as well. This also includes traited effects like Leeching Venoms. An interesting choice, but it kind of locks you into one particular build (using 3-4 Venoms, all the Venom traits, etc). Definitely worth trying at least once, though; the playstyle is pretty different.

Acrobatics

Acrobatics adds +10 Vitality and +1% Boon Duration per point spent. I prefer Vitality over Toughness in general, since armor doesn't have any effect on Conditions. Unfortunately, Thieves aren't very good at applying Boons (certainly not to allies), so it's a bit wasted.

• Adept Minor Trait - Expeditious Dodger. Gain 2 seconds of Swiftness on Dodge. This is an excellent trait that is useful in all kinds of situations. I'm very fond of pairing it with Uncatchable, which makes it almost impossible for PvE foes to catch up to me.
• Master Minor Trait - Feline Grace. Dodging returns some of the Endurance used. This lets you Dodge more often; you recover about 1/3 of a Dodge's worth of Endurance each time you Dodge.
• Grandmaster Minor Trait - Fluid Strikes. Increases damage by 10% when Endurance is not full. A really easy condition to meet, for a significant damage bonus, on a class that should be Dodging all the time anyway. Just don't get overzealous and leave yourself unable to Dodge when you really need it.

Acrobatics Adept Major Traits

• Descent of Shadows. Release Blinding Powder when you take fall damage. Fall damage is reduced by 50%. 8 second cooldown. This didn't used to have a cooldown, making it potentially really powerful. I wouldn't bother anymore, though, unless you're doing a jumping puzzle or something (the damage reduction has no cooldown).
• Power of Inertia. Gain Might when you Dodge. It's only a single stack, but lasts for at least 10 seconds (Acrobatics increases Boon duration), so...
• Vigorous Recovery. Grants 10 seconds of Vigor when you heal (have to actually use healing skill - passive Signet of Malice doesn't count). I don't really like the Vigor buff, but this does pair well with Withdraw since that is already another roll.
• Assassin's Retreat. Gain Swiftness when you kill a foe. One second cooldown. I don't know how long the Swiftness lasts, or if it triggers on killing Critters; those are important questions to ask. In theory, though, this could be pretty good. I can't seem to get this to do anything in Heart of the Mists, so maybe it's bugged...
• Master Trapper. Traps recharge 20% faster. I don't think Traps are that powerful, but if you really like them then this is a good choice.
• Fleet Shadow. Move 33% faster while in Stealth. This is not Swiftness, and doesn't stack with other speed buffs. Regardless, it's a good skill if you have multiple ways to enter Stealth.

Acrobatics Master Major Traits

• Fleet of Foot. Dodging removes Crippled and Weakness from you. 10 second cooldown. This is useful if you don't have Withdraw as your healing skill, although it doesn't remove Chilled or Immobilized.
• Pain Response. Gain 10 seconds of Regeneration and remove Bleeding, Poison, and Burning when struck and under 75% health. 45 second cooldown. This is a pretty powerful skill that greatly enhances survivability as long as you remember it's there and can generally keep track of its cooldown. Don't waste a condition removal like Hide in Shadows when it's ready to trigger, for instance.
• Quick Recovery. Gain 2 Initiative every 10 seconds. This increases overall Initiative regeneration by about 33%. Combine with Infiltrator's Signet to recover an additional Initiative every 10 seconds, making Initiative regenerate almost 50% faster in total.
• Assassin's Reward. Heal yourself every time you use a skill that costs Initiative. You're healed for an amount equal to 10% of your Healing Power per point of Initiative spent. Personally I don't find that to be a strong enough heal, especially since stacking Healing Power isn't really a good Thief strategy, but...meh. Works best with Signet of Malice to gain even more health.

Acrobatics Grandmaster Major Traits

• Hard to Catch. Shadow Step away and give 12 seconds of Swiftness when you are disabled (Stun, Daze, Float, Knockdown, Launch, Knockback, Sink, or Fear). 60 second cooldown. This trait is great for pissing people off in PvP, but it's not very practical - in fact, it can be quite dangerous, for example if you Shadow Step into an area with more enemies or such.
• Quick Pockets. Gain 3 Initiative on weapon swap while in combat. This could be used in a spike build. Also, if you weapon swap every 10 seconds, that's approximately a 50% increase in Initiative regeneration...although the resulting loss of performance overall might make that not worthwhile.

Trickery

Trickery adds +10 Condition Damage and +1% Steal Recharge Rate for every point spent. These are both good bonuses and make the trait line good on its own.

• Adept Minor Trait - Kleptomaniac. Stealing gives you 3 Initiative. Useful for spiking, although I feel bad when I open a battle with Steal and I'm already at full Initiative...
• Master Minor Trait - Preparedness. Increases maximum Initiative by 3. This is really good and I shouldn't have to explain why.
• Grandmaster Minor Trait - Lead Attacks. Increases damage by 1% per Initiative. This is a fantastic trait since you'll be passively dealing up to 15% more damage at all times.

Trickery Adept Major Traits

• Merciful Ambush. Create an Ambush Trap when reviving an ally. 20 second cooldown. This is decent, but an enemy that really wants to stop you from reviving will of course just ignore the Thief and go after you/the ally. One potential usage is to start reviving anyone, but then immediately stop and continue fighting. This gives you a free Ambush Trap every 20 seconds.
• Instinctual Response. Use Throw Feathers to Blind nearby enemies and Stealth yourself when you take more than 20% of your max health as damage in a single strike. 60 second cooldown. I don't really like this - if something hits you that hard, it's either an environmental/siege weapon that doesn't care about stealth, or it's a super strong foe that's going to kill you anyway. It doesn't truly stop spikes in PvP, either, since attacks that were already aimed at you still hit through Stealth.
• Uncatchable. Leave behind Caltrops when you Dodge. The Bleeding, Crippled, duration, and radius of the Caltrops is smaller than the legitimate skill, but this is still a really fun and powerful trait, even moreso when combined with Expeditious Dodger. The Caltrops are left at the location you dodged from.
• Flanking Strikes. +5% damage when attacking a foe from behind or from the side. Similar to Side Strike; a good skill if you can make it work, but not that easy to pull off outside of a group setting/PvP.
• Thrill of the Crime. Stealing grants Swiftness, Fury, and Might for 10 seconds to you and all nearby allies. It's only 3 stacks of Might, but this is a good trait anyway, since Fury is always useful.
• Long Reach. Increases the range on Steal to 1200. 900 is enough most of the time, and Thieves can't hit things at 1200 range outside of Cluster Bomb anyway. Still, a decent choice.

Trickery Master Major Traits

• Bountiful Theft. Stealing grants Vigor for 15 seconds to you and all nearby allies. Also removes two Boons from the target and applies them to you and all nearby allies. Vigor is mediocre, but the ability to steal Boons is pretty powerful. Removing Protection and Fury and giving it to you and allies, for example - that's great. Or how about Aegis?
• Trickster. Tricks recharge 20% faster. This includes Caltrops, Haste, Roll for Initiative, and Scorpion Wire. All of these are powerful skills, so this trait is definitely worth considering.
• Initial Strike. Attacks with the first weapon slot skill have a 7% chance to regain 1 Initiative. This works best with Daggers since they're the fastest, but I'm not sure this is mathematically superior to e.g. Infiltrator's Signet. Obviously it's more luck-based, but...
• Ricochet. Pistol shots have a 5% chance to bounce to an additional target. This is terrible. None of the Pistol's shots are individually powerful enough to warrant taking this trait, and in any case it's not reliable with such a low proc chance. Why would you use Pistols in an AoE situation anyway?

Trickery Grandmaster Major Traits

• Hastened Replenishment. Gain 4 Initiative when using a healing skill. This works best with Signet of Malice or Withdraw, since they have the shortest recharge times.
• Sleight of Hand. Stealing Dazes your target for 1 second. This turns Steal into an interrupt, which is a nice perk, but the recharge on Steal is too long for it to be really meaningful, in my opinion. I'd rather take a lower-tier skill. It does mean you can use Steal to chase a fleeing foe, though; Daze them, then apply a snare.

Gear, Sigils, Runes, Gems, etc

Gear doesn't matter at all before level 80, and I don't actually know much about gearing up, so I can't complete this section yet.

I don't know enough to write extensively about upgrade components, either. There's an incomplete guide here that you could consult in the meantime.

Builds

This is the tl;dr section that summarizes everything above into practical, useful terms.

General PvE build

This is a concept more than a specific build, since several approaches are valid here. Experiment and find which combination you like best.

1. Weapons

In PvE, you always want to have at least one ranged weapon available. I almost always prefer the Shortbow because it has AoE and utility; the main hand Pistol has a useless #2 skill, no AoE, and weak Dual Wield skills. Unload does some damage, but it's just not very impressive unless you totally spec for power, precision, and crit damage to the exclusion of condition power/damage. Even then, speccing for Unload makes Vital Shot and Sneak Attack weak. It's just not very well balanced.

The other slot should be a melee weapon, since those hit harder and do better single target DPS. (All-ranged is also a nightmare to play against foes that reflect/deflect/absorb projectiles.) Basically, you use the ranged weapon against dangerous foes like bosses, and use melee to kill generic trash mobs. You have four choices:

1. Dagger/Dagger. Daggers can be played many ways, going for power, crits, or conditions. This gives more flexibility in terms of what gear to pick up and what traits to invest in. Double Daggers gives the basic chain + Backstab, Heartseeker, Leaping Death Blossom, Dancing Dagger, and Cloak and Dagger. The basic chain + Backstab and Heartseeker are already pretty good on their own. Leaping Death Blossom is a multi-purpose attack which is rather useful. I don't use Dancing Dagger very often, although if weapon swap is on cooldown it's my only ranged attack. Cloak and Dagger is expensive, but having Stealth ~whenever you want it is a very powerful tool. Finally, this set gives you access to three separate Finishers, which gives a lot of options when combo fields are used.
2. Dagger/Pistol. This set gives you some defensive options at the cost of some power. Shadow Shot replacs Leaping Death Blossom, but isn't very useful in PvE. Headshot, a reliable, fast interrupt, and Black Powder, a pulsing PBAoE blind, make up for it somewhat. These skills don't work too well on bosses, unfortunately...but for generic trash they're great. You can combo through Black Powder's Smoke Field with Heartseeker to grant yourself Stealth (although it will cancel as soon as Heartseeker lands, so best for things like Shadow's Embrace).
3. Sword/Dagger. Swords focus on Power, Precision, and Critical Damage. The inherent AoE of the Sword on the basic chain is good for cleaning out trash mobs. Tactical Strike and Infiltrator's Strike are more PvP-oriented...Flanking Strike works well when it works, so if you have confidence in your refexes it's worth trying out. Other than that, no particular synergy with the Dagger; if you ever needed to hit something at range, Infiltrator's Strike is generally a better way to do it. Cloak and Dagger is still good, but Tactical Strike isn't a very appealing way to use it.
4. Sword/Pistol. This gives you Pistol Whip, which hits really really hard. Headshot and Black Powder are useful, as described above.

2. Healing, Utility, and Elite Skills

The choice of healing skill depends on the situation and what specific traits you pick.

• Hide in Shadows gives the biggest heal, removes damage over time conditions, and doubles as Stealth. More useful for later stages of the game where conditions are more common and actually hurt.
• Withdraw is available much more often and breaks movement impairment, and doubles as another roll. More useful early on before conditions start to hurt a ot.
• Signet of Malice is similarly fast (even faster with Signet Use trait) and lets you heal over time with every attack. It won't save your neck like the other two in a pinch, but if you play defensively, Signet of Malice ensures that you don't need a big heal in the first place.

Almost all of the Thief utility skills have some use in PvE. The only exceptions are Assassin's Signet, Shadow Trap, and Haste; these really belong in PvP only. Needle Trap is just bad. The following three skills are just my personal favorites; you should experiment with the other skills to see if you like them more.

• Signet of Shadows should be stapled to your bar at all times. Even with Waypoints, there's a ton of running around to do in PvE, and this skill will save you hours (or days, or weeks, or...) of playtime. Speed is useful in combat, too: being more maneuverable makes it easier to avoid attacks and close distances. Alternatively, if you don't want to fight things, Signet of Shadows generally lets you run right past (melee) foes without them being able to touch you and force combat. It also doubles as a last-resort AoE Blind if you need it.
• Caltrops is a wonderful skill, even without increased condition duration/damage. PvE foes have a tendency to just blindly run through the Caltrops, crippling them for a year and a half while you're already halfway across the map. The AoE damage from Bleeding is not bad, either. This becomes less useful when you're fighting mostly ranged attackers, though.
• Shadow Refuge is a powerful panic button that can save your life in many situations. Going Stealth breaks aggro (after a mob finished whatever they were doing) and this lasts at least 12 seconds, so most foes will lose interest and go back to their original location after you cast Shadow Refuge. Works even better with traits that enhance Stealth, but still a good option regardless.

Caltrops and Shadow Refuge don't work underwater. I honestly don't know what to take to replace them, though; none of the available choices are nearly as useful underwater as they are on land, except Roll for Initiative which has a long cooldown. I'd probably take Roll for Initiative and Signet of Agility just to maximize the number of dodges I can get.

Finally, the Venom skills should not be used outside of a Venomous Aura build, at least in my opinion. You're welcome to experiment and see if you find them useful, but I don't find them to be powerful enough...other skills are more worthy of a skill slot.

As to Elites...Thieves Guild is better when facing small numbers of foes, while Dagger Storm is better against large crowds (although it's also more dangerous). Don't bother with Basilisk Venom at all; it's the only underwater Elite, but if you're lucky enough to be a Norn, the transformations are better.

3. Traits

Each of the Thief trait lines offers something useful, so there are a lot of possible combinations. It's common to pair Power, Precision, and Critical Damage; Condition Damage and Condition Duration; or Toughness, Vitality, and Healing Power. Those are just archetypes, though - feel free to mix and match.

• Don't take more than 25 Deadly Arts if you're using that line. The Grandmaster Major Traits aren't worth it, and there aren't enough good lower-tier Traits to justify the 3rd slot. Mug and Dagger Training/Combined Training are the ones you want. Would recommend taking at least 15 points to get Lotus Poison, though. Exposed Weakness is very good, but those extra 10 points could be invested elsewhere too.
• Critical Strikes is good at any amount, since it improves both Precision and Critical Damage simultaneously. If you want to invest the full 30 points, Executioner is amazing. For the other two slots I'd take Concealed Defeat and Combo Critical Chance, probably. Signet Use is also good when combined with Signet of Malice. Otherwise, Practiced Tolerance is a filler option.
• Shadow Arts is all about survivability, and it has a lot of neat tricks to help avoid damage. Especially in PvE where you can't count on being revived by teammates, it's important to be able to take care of yourself. The Minor Traits aren't amazing, but each of the Major Trait tiers opens up a bunch of fun possibilities, and there are dozens of ways to combine them effectively. 30 Shadow Arts also unlocks the legendary Venomous Aura build, which I'll describe later.
• Acrobatics is ... interesting, but it doesn't have a lot of unconditional, always-useful traits that combine well with everything. The Vitality is alright, but Boon Duration is mediocre for a Thief. I recommend at least 5 points to get Expeditious Dodger, but not sure about investing further.
• Trickery lets you Steal more often, and it has very powerful Minor Traits. Uncatchable, Thrill of the Crime, and Bountiful Theft are the best Major Traits, but there are uses for Trickster and Hastened Replenishment as well. Initial Strike can be good with Daggers if you're lucky, and in a group setting Flanking Strikes is great, but these are more luck-based than the others.

If you wanted to know my personal preference, I like to take 25 Deadly Arts, 10 Shadow Arts, 5 Acrobatics, and 30 Trickery:

• Serpent's Touch, Mug, Lotus Poison, Dagger Training, Exposed Weakness.
• Last Refuge, Shadow's Embrace (can swap for anything else if no dangerous conditions).
• Expeditious Dodger.
• Kleptomaniac, Uncatchable, Preparedness, Thrill of the Crime, Lead Attacks, Bountiful Theft.

This lets me maintain Poison and Weakness, deal bonus damage all the time, do a million things at once with Steal, and run away fairly easily. I have Power, Condition Damage, and Condition Duration; I rely on more steady damage than big crits to kill things. For me, Dagger/Dagger and Shortbow are the weapons of choice.

4. Gear and Upgrades

I'll have to fill this out some other day, because I don't really know much about this aspect. Without researching it too deeply, my personal preference would be 6x Rune of the Adventurer and some form of Carrion gear. For Sigils I'd go with 2x Sigil of Force on the Daggers and Sigil of Water on the Shortbow. There are probably better specific options but I haven't looked too closely at them.

5. Venomous Aura

This is a special build that uses (obviously) Venomous Aura, 3-4 Venom skills, and all the Venom-enhancing traits. The nice thing about Venomous Aura is that the bonuses you're giving out can benefit even useless NPC helpers...as long as they can land attacks, they'll make use of your buffs.

• Devourer Venom, Skale Venom, and Spider Venom are generally best. Ice Drake Venom (in my opinion) isn't as good as Devourer Venom, since skill recharge rarely matters for foes (actually, not sure it affects them at all). Basilisk Venom can also be taken, but depending on the situation Dagger Storm could still be more useful.
• You need 30 points in Shadow Arts to access Venomous Aura. Leeching Venoms is also in Shadow Arts, so take that as well.
• 30 points go into Deadly Arts. You'll take Quick Venoms, Residual Venom, and Venomous Strength.
• The other 10 points should probably go into Trickery for Condition Damage, since they aren't particularly useful in Critical Strikes or Acrobatics.
• Get near your allies and cast one Venom. Wait for it to be used up (at least on yourself, hard to keep track on allies) before casting another, otherwise you'll forfeit some uses of Leeching Venoms. If you do blow them all at aonce, you'll have 6-8 stacks of Might on everyone for 20 seconds...but spreading them out lets you maintain Might longer.
• Your enemies will suffer from long-lasting Poison, Weakness (you have Lotus Poison), Immobilize, and a bit of Vulnerability. If you add Basilisk Venom, random petrifications happen too.

In an ideal situation, Venomous Aura would be used with yourself + 4 allies (the max targetable with AoE), against a single foe so that the effects stack, and preferably not against one with Unshakable; otherwise, the Weakness and Vulnerability will wear off fast, and the Immobilize and Petrify might not work at all. The effects are less noticeable against multiple foes, but it can still cause some chaos.

PvP Builds

I don't do PvP, I only read about it (WvW isn't really PvP). Anything here is strictly theoretical since I haven't tested it yet.