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