Full list of all 101 Skul: The Hero Slayer achievements.
The base game contains 57 achievements, and there are 5 DLC packs containing 44 achievements.
Defeat the First Hero without getting hit
Die from a trap
Defeat the First Hero as Little Bone
Defeat the First Hero without saving the stage NPC
Stay in the black market for 5 minutes
Acquire Ghoooooul
Acquire Vanguard Captain
Keep talking to Headless
Acquire Demolitions Expert
Acquire Soul Knight
Acquire Defender Captain
Acquire Carleon Commander
Acquire Elder Ent Skull
Acquire Nightmare
Acquire Dark Alchemist
Acquire Gold Gargoyle
Acquire Eternal Mummy
Restore the Demon King Castle to its original form
Defeat St. Joan II without getting hit
Defeat the Leiana Sisters without getting hit
Acquire Joker
Acquire Frozen Spirit
Acquire Eternal Werewolf
Defeat Chimaera without getting hit
Acquire Super Rock Star
Acquire Desperado
Acquire Minotaurus III
Reach the top of the chandelier in the Demon King Castle
Acquire Royal Guard Captain
Acquire Devil Berserker
Acquire Neo Samurai
Keep restocking from the collector
Reach the top of the throne in the Demon King Castle
Acquire Magnifico
Acquire Sniper
Acquire Master Ninja
Defeat Yggdrasil without getting hit
Acquire Warlord
Rescue the Demon King and return to the Demon King Castle
Defeat the Sword of Carleon, the First Hero
Kill 100 adventurers
Acquire Poseidon
Acquire Dark Avenger
Defeat the archbishop of the Leonia Order, St. Joan II
Acquire Yaksha
Acquire Destroyer
Acquire Gambler
Acquire Abyssal Monarch
Defeat the distorted goddess, Chimaera
Defeat the adjutants of the Gold Mane Knights, the Leiana Sisters
Play on Rookie Mode
Acquire Champion
Acquire Grim Reaper
Defeat the elder ent, Yggdrasil
Acquire Arch Lich
Stay in the black market for 1 minute
Return after experiencing death