Full list of all 12 Torchlight achievements worth 200 gamerscore. It takes around 10-12 hours to unlock all of the achievements on Xbox 360.
Defeat Medea
Defeat Alric
Achieve maximum fame
Successfully enchant one item 10 times
Defeat Krag
Successfully enchant one item 5 times
Defeat the Ember Colossus
Defeat the Root Golem
Defeat the Overseer
Defeat Brink
Send your pet to town
Change your pet by feeding it fish