Ok so in the episode "CurseWorld Part I", right after Morro said "we must not let our guard down!", Some ghosts that were around started floating up and raising their hands like they were gonna summon something, a few seconds later a ghost dragon fly a over to The truck that Wu and Misako are in, then a few seconds later, the camera goes to a whole group of these ghost dragons. So I'm thinking that the ghosts summoned these ghost dragons with the element of Ghost Energy!. So thus they aren't ghost dragons, they are "Ghost Energy Dragons" so they should be put in the Catogory of "Elemental Dragons" and not normal dragons.