Infected World Crystal

An Infected world crystal is a world crystal that has a slug on it.

The larval slug burrows into the world and wraps itself around the world crystal. It will then infect the world crystal. Over time it will corrupt the entire crystal, at which point it becomes capable of literally consuming the world crystal. The slug then enters a pupal state before emerging as a spacefaring creature. It then consumes the husk of the world and goes forth into the multiverse seeking other worlds to devour.

A world with an infected world crystal at its core produces a not so idyllic world for its inhabitants. In addition to the usual Elves, Dwarves, Humans and Halflings these worlds produce copious monstrous peoples. These infected worlds produce D&D worlds, wild and dangerous, where life is precarious and the good are matched by the evil.