Here is the full list of all 31 EvilQuest achievements.
Beat the game on Normal
Kill 750 enemies
Eat 3 Whole Chickens
Open The Lightning Seal
Obtain a portrait of Galvis
Murder 5 deserving NPCs
Kill King Jerric
Open The Fire Seal
Open The Ice Seal
Open The Earth Seal
Kill King Jerric's top general
Learn Ice1 and kill your teacher
Beat the game on Difficult
Kill 50 enemies with Fire2
Kill 5 enemies at one time with Lit2
Freeze 30 enemies with Ice
Kill 4 enemies at one time with Earth2
Kill 8 enemies at one time with Shadow2
Equip all Dragon Gear
Kill 1500 enemies
Kill 100 Dragons
Eat 10 Hams and 10 Steaks
Eat 75 Pieces of Food
Reach a Toughness level of 35
Reach a Strength level of 35
Reach a Vitality level of 35
Reach an Intelligence level of 35
Equip all Chaos Gear
Give 1000 GP to a dancer
Equip The Invisibility Cloak
Equip The Amulet of Magic