Here is the full list of all 22 Infinite Dungeon Crawler achievements.
You have hit level 5!
You have hit level 10!
You have killed 50 giant rats!
You have played a main character as all 8 classes and leveled each up to level 5!
Congratulations! You have slain 100 monsters!
As a Paladin, you have slain 100 undead creatures!
You're well on your way now to becoming a master monster-slayer!
Your love of fire shows as you have used 50 fire abilities!
Your love of the cold shows as you have used 50 ice abilities!
Your love of electricity shows as you have used 50 shock abilities!
You have hit level 20!
You have slain 50 beasts!
You have slain 50 flying creatures!
You have won money while gambling 10 times (we won't talk about how many times you lost money)!
You have taken on 50 jobs. You may not have always succeeded, but at least you tried!
You have shown your devotion to the Old Gods by praying at the Church 25 times!
May the Old Gods bless you. You have given alms 25 times!
You have ventured through The Gate to other worlds 50 times!
You have sold 50 loot items!
You have picked and sold 50 mushrooms!
You have found and sold 50 gold nuggets!
You have killed 50 skeletons!