Vanquish

Description
To vanquish an explorable area is to kill every creature in that area while in Hard Mode, even if some mobs do not show up in the radar. This includes pop up mobs that appear when you travel within their aggro range.

Players earn an extra 5 XP and 3 gold per enemy defeated after they finish vanquishing an area.
 * Example: In Plains of Jarin a player needs to kill 209 foes to vanquish an area, which results in that character getting an additional 1045 XP and 627 gold when completed.