If they get far enough out into the multiverse, Homo drakensis are eventually going to meet one or more of the other post-human conqueror species on the Tree of Futures: the Sauron Supermen, the Phaestor Vampires, the Morthan, the Kolnari (to name just the ones I can think of off the top of my head). But that's not what makes this crossover one that Should Not Be...
...it's the prospect of them joining forces with their counterparts.
...it's the prospect of them joining forces with their counterparts.