The Dungeon That Started It All

Ordis was expecting a second chance at life—maybe as a hero, a demon king, or at least something with arms. Instead, he wakes up as a small cave in the ground.  Correction: the Big Cave as he actually have floor within as people entered the small cave. The first and only dungeon to ever exist on Earth. Now, governments are panicking, and scientists are having existential crises.  Oh, and apparently, his mere existence is causing magic to return to the world? Whoops. A new job like adventurer and dungeon expert to be created!  With his "Primordial Dungeon System", Ordis can evolve, absorb invaders, and reshape himself into the most absurdly overpowered labyrinth in history. Will he become a benevolent dungeon, a world-ending catastrophe, or just an eternal troll who makes adventurers suffer?  One thing’s for sure—Earth better start adapting, because there’s a new living being in town.