This quest has three stages: level 37, 40 and 44. Each stage must be completed 10 times before the next will be made available. The quests of the final stage, level 44, have a cool-down of one hour before the next quest can be offered.
If you desire a different target monster, delete and reacquire the quest.
Slay a number of creatures in The Feerrott, randomly assigned from this list. All these can be found in the southeast of The Feerrott on the path to The Temple of Cazic-Thule. There is a cool-down timer of 60 minutes from completion to when Zozor will offer the quest again: