ZirHarpy's Lair

They are hybrids between the shade and dragons, these creatures take over the minds and bodies of dragons, once the parasite takes over a host, it devours their sanity and leaves the host violent and aggressive, loosing all sense of self. Once the parasite leaves the host, it makes the host follow them to protect them from other dragons, for when other find out about a parasite infection, they try to kill the host carrying it, resulting in the parasites gathering a horde to protect themselves.