Gestasite

The Gestasite are a species of mutualistic Elder Dragon that form large mobile gestalts, often making massive bodies that crush larger predators with sheer weight. They usually gestate in groups of hundreds within large monsters, like Lagombi, gaining traits of their host. If they mature, or the host dies, the eggs will hatch, burst out of the host whilst consuming its flesh, and shape themselves into a crude approximation of the host, linking themselves together into a complex system of worms, the larger females forming the main body, while the hundreds of stronger males forming the limbs, claws, and armor.

Biology
A single Gestasite is a writhing, worm-like creature, usually black in color, with a single yellow eye spot. In their gestalt form, they form a shimmering, black mass of worms and yellow eye spots that are constantly splitting, shifting, and growing, becoming a massive mass of tentacle-like worms that devour any organic matter in their path, using it as fuel to make more worms.

They reproduce via a fertilized female worm burrowing into a sleeping Monster's flesh, laying hundreds of eggs, and watching over their brood, slowly consuming their host's flesh. The female will control the host, making them aggressive and insatiable, constantly consuming meat to fatten the host while the eggs incubate. Eventually, the eggs will start to hatch, and the host will be driven into a state of ultra violence, eventually dying.

Gestasite Gestalts often gain the attributes of their hosts, becoming a Specialist Gestalt. For instance, a Gestalt forming from a Lagombi would be called a White Rabbit Gestalt, gaining intense cold resistance and intense ice-type attacks that are stronger than their host.

Behavior
Singular Gestasite are very rare and shy, often hiding away in dark crevices. Gestasite gestalts are aggresive, often devouring their host's predators and creating more mass for the gestalt as a whole.