Here is the full list of all 14 Terrible Beast from the East achievements.
Reach Level 10
Reach Level 40
Reach Level 60
Defeat Inbred Brawler
Defeat Unholy Soul Protector
Defeat Bone Blesser
Defeat Fluffy Webster
Defeat Nameless Skull Knight
Defeat Captain Baltazar Eeston
Collect 1000 Souls
Collect 10K Souls
Collect 100K Souls
Craft Your First Weapons
Reach Level 80