Here is the full list of all 38 Deathstate achievements.
Start and end a boss fight with only one hit remaining.
Find a Demon or Horror aspect stone.
Enter the Maze of Ix.
Beat a level without taking damage.
Enter the Ossein Swamp.
Escape a level after time has run out.
Enter the Fortress of Koth.
Unlock all playable characters.
Punch the final boss as the Brawler.
Beat the game as the Embalmer.
Collect three eye organs as the Eye.
Beat the game as the Skeleton King.
Turn into a Demon as the Priest.
Gamble with the Merchant as Scar.
Drink 10 potions as the Scientist.
Teleport 20 times in one game as the Starcreep.
Find and equip 5 different grimoires in a single game as the Seeker.
Die at Depth 1 as the Embalmer.
Die in the first minute of gameplay.
Resurrect 30 or more enemies with a single Awaken potion.
Kill a boss while under the effects of a Hot Blood potion.
Kill a boss while under the effects of an Introspection potion.
Beat the game without picking up a weapon item.
Beat the game without picking up a grimoire item.
Beat the game twice sequentially.
Beat the game.
Beat the game at maximum Desecration.
Beat the game without taking damage.
Kill an Elite enemy after time runs out in a level.
Enter the Lost Arcanium.
Enter the Dark Realm.
Find 500 gold in one run.
Die 100 times.
Play the game for a combined total of 24 hours.
Have 20 or more organs at one time.
Unlock all bestiary entries.
Find at least 140 unique items.
Unlock all other achievements.