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