Hundreds Years After I Was Called [Just Corpse], I’ve Become Strongest Undead When I Woke Up

Zion, a solo adventurer, recklessly entered a dungeon beyond his ability. Alas, that was the last thing he did. Wandering inside a dungeon for hundreds of years, as an undead, he kept advancing into the dungeon. Slaying monsters left and right until his undead body underwent ‘evolution’ many times over―― ――By the time he regained his ego, he had already become the strongest undead: 【No Life King】. Humankind, who was made aware of the appearance of a new world-class disaster monster, felt dread as they fell into the abyss of despair. 「The world is… done for.」…Or so they think. 「It’s okay, do I look like an evil undead to you?（Smile~）」 「「「HIIIIIIIIIIIII?!」」」 「…SOMEONE PLEASE TELL ME WHYY...