Ryland Grace is the sole survivor on a desperate, last-chance mission—and if he fails, humanity and the earth itself will perish. Except that right now, he doesn’t know that. He can’t even remember his own name, let alone the nature of his assignment or how to complete it. All he knows is that he’s been asleep for a very, very long time. And he’s just been awakened to find himself millions of miles from home, with nothing but two corpses for company. His crewmates dead, his memories fuzzily returning, Ryland realizes that an impossible task now confronts him. Hurtling through space on this tiny ship, it’s up to him to puzzle out an impossible scientific mystery—and conquer an extinction-level threat to our species. And with the clock ticking down and the nearest human being light-years away, he’s got to do it all alone. Or does he?

Welcome to the Gun Show! The top ten list is populated. The sponsorship program is open. The difficulty is ramping up. The first three floors were nothing compared to what Carl and Donut now face. The Iron Tangle. An impossibly-complicated subway system built out of the world's subterranean railway systems, all combined and then tied together into a knot. Up is down. Down is up. Close is far. The cars are filled with monsters, the railway stations are less than safe, and the exit is always just a few stops away. But there is hope. For the first time, the crawlers are all working together. The loot is better than ever. And the secret to unraveling it all may be hidden in the pages of a seemingly-useless book. Welcome, crawlers. Welcome to the fourth floor of the dungeon.

Welcome to the Gun Show! The top ten list is populated. The sponsorship program is open. The difficulty is ramping up. The first three floors were nothing compared to what Carl and Donut now face. The Iron Tangle. An impossibly-complicated subway system built out of the world's subterranean railway systems, all combined and then tied together into a knot. Up is down. Down is up. Close is far. The cars are filled with monsters, the railway stations are less than safe, and the exit is always just a few stops away. But there is hope. For the first time, the crawlers are all working together. The loot is better than ever. And the secret to unraveling it all may be hidden in the pages of a seemingly-useless book. Welcome, crawlers. Welcome to the fourth floor of the dungeon.

"The training levels have concluded. Now the games may truly begin." The ratings and views are off the chart. The fans just can't get enough. The dungeon gets more dangerous each day. But in a grinder designed to chew up and spit out crawlers by the millions, Carl and Princess Donut need to work harder than ever just to survive. They call it the Over City. A sprawling, once-thriving metropolis devastated by a mysterious calamity. But these streets are far from abandoned. An undead circus trawls the ruins. Murdered prostitutes rain from the sky. An ancient spell is finally ready to reveal its dark purpose. Carl still has no pants. They call it Dungeon Crawler World. For Carl and Donut, it's anything but a game.