Crawler

Crawlers reach the World Dungeon through entrances that are marked and easy to spot, 150,000 of them for the first level alone. Each level down has half as many entrances as the one above it, 75,000 for the second and 37,500 for the third. On every level a crawler has to find a staircase down before time runs out. Whatever matter is left behind, organic or not, is forfeit when the level is reclaimed. The time limit on the first level is five rotations of the planet, and every lower level has a longer one.

Each crawler is given a number, a crawler name, a race and a level, all shown in an information box. Carl is Crawler Number 4,122, a level 1 Human, and the cat Princess Donut is Crawler #4,119. A new race and a class become available on the third floor. The opening announcement strongly advises finding a tutorial guild right away, and such guilds are seeded through levels 1 to 3.