Personality is a semi-retired hidden roleplaying mechanic that affects a character's interactions with NPCs in the world. The initial personality is determined by how the player answers biography questions during character creation and is refined by the most recent 100 encounters with particular NPCs.
Most aspects of the personality system were hidden with the introduction of the April 2014 Feature Pack and September 2014 Feature Pack. Since then, this mechanic has little to no presence in the game and doesn't produce any noticeable gameplay effect.
The remaining parts of the system include choice of personality during character creation and dialogue interactions with certain NPCs. Most of such NPCs are found in personal story or provide speed boons in cities. While the choices made by the player still affect personality, currently there is no way to see the character's personality scores.
The game keeps track of three aspects of personality: Charisma, Ferocity1 and Dignity, whose sum is 100%. Dialogue choices are able to affect the personality by increasing one aspect and thereby decreasing the others. For example, constant bullying of shopkeepers might increase ferocity to a point that the character becomes barbaric. Similarly, frequent cunning will lead to a reputation as a scoundrel.
Personality affects gameplay by offering certain dialogue options only to some types and altering the reactions of certain NPCs. However, the game was designed to avoid extreme consequences, i.e. players are able to take on different personality types without fear of losing out on overall rewards or benefits.
There are 10 different personalities a character can take on. Until the April 2014 Feature Pack, the personality icon was next to the profession icon on the hero panel and showed which personality the character had at that time. The only way to find out about a character's current personality is through unique dialogue choices with NPCs. The character's initial personality selection may be displayed using the hero panel by selecting Story Journal, "My Story" then "I'm ..."