Mongolian Death Worm

A ring of tentacles surrounds the wide, gaping mouth of each worm, and inside sit several rows of teeth, set into a long body marked with snake-like patterning. Okarun pegs an ordinary one at somewhere between 1.5 and 2 meters, and they count as huge creatures. The specimen the Kito Family tended across two hundred years grew larger than that norm.

Dwelling below ground, the worms live in symbiosis with germs and bacteria, and that heavy metabolic dependence on microbe-rich surroundings leaves them badly exposed to ultraviolet light. Brief contact with the sun dries them out quickly and shrivels them, yet this only disables rather than kills, which is how Naki could parch one for smuggling and then bring it straight back with a splash of water. They eat meat, and the more calories they take in the faster their mass balloons. Naki Kito notes that feeding on people is what unlocks their innate powers, so the Byakuja Village hatchling, raised on livestock, never matched the strength its parent had.

For better than two centuries a Mongolian Death Worm made its home inside the Byakuja Village volcano, woven so tightly into village life that locals took it for the fabled Tsuchinoko, honoring and fearing it as the cause of the eruptions that menaced their homes. To keep the magma at bay and the creature growing, the Kito Family kept up a custom of offering up their own community's children to it. That cruel arrangement collapsed when their newest sacrifice, Momo Ayase, drove the worm above ground, where the sunlight desiccated and killed it. Its death set off the volcano, and Momo and Chiquitita stopped the disaster by cooling the lava with the cadaver's chilly phlegm. Naki Kito afterward came across eggs the worm had laid, hatched one, and raised it on livestock, which bulked it up but left it without its parent's gifts.

He dried the grown hatchling for travel and slipped it into the cargo hold of Momo's Shimane-bound flight, reviving it midair to take on the Typhoon Human inside Empty Space. Per Seiko's scheme, the worm gulped the frozen sharks the storm had drawn in and spat them back to chill the vapor feeding the enemy, while Momo turned it into a carp windsock the group could ride. Once the Typhoon Human went down, the Evil Eye seized control and booted a megalodon that had gulped the hatchling and the Kitos clean out of orbit, meaning to kill them; the group ended up on the moon, where the worm shadowed the Kitos as they again swore vengeance on Momo.