Sum Viewer is an achievement within Heart of Thorns that grants a mastery point. It can be obtained in the Exhumed Delve area of Dragon's Stand.
|Sum Viewer||Dragon's Stand||11|
|Catch a glimpse of Rata Sum in the distance.I can see my college from here!||Spotted Rata Sum||1|
The location to gain the achievement and mastery point is Northeast of the Southern Forward Camp Waypoint, located on the far East side of the Exhumed Delve in Dragon's Stand.
Head southeast from the Pact Base camp towards the Southern Forward Camp Waypoint on the East side of the map, or go right to the waypoint if you already have it. Slightly northeast of the Southern Forward Camp Waypoint is a point of interest, Rata Novan Remnants. Walk north from the waypoint and curve east towards the rock wall and point of interest, where you will encounter a bouncing mushroom (refer to the map and screenshot on the right).
Using the bouncing mushroom will bounce the user up to a short path that continues East. follow the path to acquire the mastery point.