Here is the full list of all 24 God Mode achievements.
Kill 25 000 creatures
Purchase all upgrades
Complete any map on Platinum difficulty
Complete all maps on hardest difficulty
Buy Super Pants
Reach the final level and attain God Mode
Kill 20 creatures using the Hammer ability
Trigger 20 Mage seals
Survive the "Death" Test of Faith
Destroy 50 scarab eggs before they hatch
Grind 50 creatures using the Buzzsaw melee attack
Enrage 10 Cyclops
Fully upgrade one weapon
Finish any map with 3 or more active Oaths
Kill 50 enemies using melee
Kill 2500 creatures
Complete any map without dying
Decapitate 100 Skeletons
Complete your first Oath
Purchase your first weapon upgrade
Finish any map on any difficulty
Kill 100 creatures
Finish any map with 6 active Oaths on hardest difficulty
Collect 5 000 000 unspent gold