Pusillin The Thief

If you're doing this instance to complete all the quests in Dire Maul you must talk to this guy and chase him through the instance before you can kill him.

He is to the left of the main entrance standing where the pathway is broken, you'll have to talk to him 4 times before he runs up a set of stairs to the area where you talk to him a final time and he summons about 6 imps to attack you.

If you chose not to talk to him, you won't be able to kill him and get the quest item needed.

Ooooo I hate this little guy! The only thing more satisfying than punting a gnome would be punting this brat. After picking up the quest he's to your immediate left. Talk to him. He gives you lip and then runs away. When he stops, talk to him again. Rinse and repeat. At the end he summons "friends" to attack you. It might help to mark him with a raid marker.

For anybody who wonders what that key is hes talking about all the time.

Pusilling used to be the holder of the Crescent Key, needed to enter the West and North part of Dire Maul (plus back entrance).

Apperently Blizzard found new use for him with this quest but could not be bothered (?) to change his dialogue.