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