The The Tinkerer's Lab Mission Pack Add-on for Dungeon Defenders has 4 achievements.
You Defended the Tinker's Lab and cleared the way for EV's upgrade!
You Defended the Tinkerer's Lab and cleared the way for EV's upgrade... on Nightmare!
You assaulted the Lab and eliminated the squad of corrupted EV's!
You assaulted the Lab and eliminated the squad of corrupted EV's... on Nightmare!