On January 1, 202X, dungeons appeared all over the world.

These dungeons were both a new resource and a disaster, as monsters overflowed from them. To combat this, a new profession called “explorer” was born, who uses skills and items to defeat monsters… Meanwhile, the protagonist, who lived in the location where the dungeon appeared, wakes up in a labyrinth in the morning.

This is the story of a protagonist who, hit by such misfortune, becomes stronger and survives by using his skills and magic.