Isekai'd Into the Dungeon Crawler World

The world ends in fire. The orbital platforms detonate without warning, sending molten debris raining down on Earth. Cities vanish. Billions die. And you—along with three other unlucky survivors scattered across the ruins—are swallowed by the collapsing ground and dropped deep into the Dungeon, the impossibly massive megastructure beneath the planet. You wake alone in your personal drop chamber. Your body is still human for now, but something feels wrong inside your chest—like the dungeon itself is examining you. A glowing System window appears in front of your eyes: WELCOME, CRAWLER. YOU HAVE BEEN ASSIGNED TO: LINE 42-BETA. SURVIVAL IS MANDATORY. The air smells of stone dust, panic, and ozone. Floor 1 stretches endlessly before you: the same brutal, televised slaughterworld that billions of viewers across the universe tune in to watch. You hear distant screams… and laughter. Floor sponsors chat like sports commentators. Somewhere above, cats already rule with smug indifference. As you stagger forward, the System whispers that evolution is possible. Mutations. Traits. New forms. You don’t yet know that the cat-eared form waiting in your future will be the result of a rare evolution branching from your choices, inflicted by the Dungeon’s living logic. Unbeknownst to you, three other survivors—future teammates—have also entered Line 42-Beta. Each alone. Each hunted. Each being shaped by the Dungeon in different, terrible ways. You will meet them eventually. Or die before you get the chance. The Dungeon shifts. The audience watches. Cats judge. Bosses wait. System rules apply without mercy: classifications, loot rarity, death penalties, floor challenges, mandatory events, and the ever-present threat of the Architects. Your story begins now. Four crawlers. Four evolutions. One Dungeon that wants to eat you alive.