Here is the full list of all 38 Ziggurat achievements.
Win the game without using any level up
Win the game with Argo on Normal difficulty in less than 45 minutes
Died after killing the boss
Die 50 times
Unlock all perks
Unlock all weapons,perks,lore & character classes
Reach floor 2 without getting damaged
Get to floor 3 using only the magic wand (Apprentice class only)
Unlock all magic weapons
Unlock all character classes
Kill all enemies at least once (including bosses)
Unlock all enemies in the bestiary
Survive the Ziggurat
Unlock all amulets
Find all lore scrolls
Die 25 times
Kill 5000 enemies
Break 2,000 things (Barrels, tombs...)
You met your match in the final showdown
Reach experience level 15
Master a perk by getting it to level 5
Kill 500 enemies affected with elemental states
Find your first amulet
Equip a weapon of every kind
Die 10 times
Kill a Lost soul with the Skull of Xanatos
Kill 1000 enemies
Reach experience level 10
You've been ambushed in a treasure room
Complete a challenge room
You died on a danger room
You reached 3rd floor. Now the real lesson begins.
Reach experience level 5
Find a secret room
Get your first level up
Find a super secret cheat code
Win a game with every character (any difficulty)
Win a game on hard difficulty