A soul-crystal-powered device that births a ghoul for every mob death on the floor — turning the DT plague into a perpetual monster engine.
Ghoul Generators are soul-crystal-powered devices seeded at certain The Iron Tangle stations (station 12 for jikininki, station 72 for Blister Ghouls, among others). Each spawns one ghoul for every non-undead mob that dies on the floor — a catastrophic rule given that the entire floor's population is dying of the DTs, making the generators a near-perpetual monster engine that will soon flood every line. Carl recognizes the soul crystals as the same volatile power source used for the third floor's swordsmen and Miss Quill's spell — the very kind that overloaded into his Doomsday Scenario bomb — so they cannot simply be blown up.
Elle McGib's manager suggests Carl "pull a Carl" and destroy a generator room, but the soul crystals make that its own hazard; the crew opts to hold generator-free station 36 instead.
A soul-crystal-driven spawning device housed in a station room; multiple types exist, the station-72 model "top of the line."
The floor's monster-spawning infrastructure — the mechanism turning the DT die-off into an endless ghoul flood.
Also appears in books you've already read — spoiler-safe to their endings: