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