Here is the full list of all 13 DeathSpank: Thongs of Virtue achievements.
Convince an Orque Guard you are an Orque
Kill the Evil Nun
See all 20 of Madame Primp's Outfits
Get an Engineering Degree
Go Sailing in a Pirate Ship
Learn to Speak Japanese
Kill 3000 Enemies
Kill Wortten
Reach Level 20
Discover all 44 Teleporting Outhouses
Kill Santa Claus
Watch Both Game Endings
Kill the Taking Tree