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