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.
Successfully enchant one item 5 times
Defeat Brink
Change your pet by feeding it fish
Send your pet to town
Defeat the Overseer
Defeat the Root Golem
Defeat the Ember Colossus
Defeat Krag
Defeat Medea
Defeat Alric
Successfully enchant one item 10 times
Achieve maximum fame