The quests are "endurance" sidequests, requiring the killing of a certain number of a specific Mimic each day over the course of three days. Note that they do not have to be consecutive days. The most notable reward for completing an Extermination Quest is the Mimic's Deluxe Trophies, but they also reward some Nidarian Points. Extermination Quests are split into two categories: From version 0.9.05, enemy kills in co-op count towards extermination quests.