While the Aestari Age of Wonder was flowering in the surface of Mythron, a more sinister development was unfolding beneath it. The Inxikrah had embraced with great enthusiasm their role as the apex predator of the underworld. And as their supremacy became unquestioned, their thirst to exercise it became unquenchable.
Powered by the magic of crystals of the Black Amethysts, the Krah'Zul transformation that followed each act of predation not only conferred on the Inxikrah the strengths and abilities of their prey - it flooded the predators with physical pleasure that bordered on ecstasy.
Over time this magnified and exaggerated their primal, predatory instincts. The male Inxikrah and female Inxykree both came to be driven by an insatiable, all-consuming hunger for the feeling of youthful rejuvenation that came from killing. The gnawing addictive power of the crystals, and their growing scarcity, caused infighting among the Inxikrah. A system of rigid castes was established to create order, to preserver the crystals, and to help the Inxikrah survive and remain preeminent in a world fraught with danger and dwindling resources.
The elation and the rush of killing and transformation became a ritual, taking on a sacred significance that made the Inxikrah even more rapacious. The male Inxikrah became increasingly defined by an ethos of cruelty. Lesser sentient creatures and captured enemies from raids became slaves or playthings, including the Inxikrah's less evolved cousins, the Serpenti, which the Inxikrah often tranformed into tortured Darkspine Elementals and familiar-like wraithlings.
Meanwhile, the female Inxykree grew more social and increasingly repulsed by the Inxikrah's random brutality. Over generations the, the differences became so pronounced they were like two separate species, the male Inxikrah and the female Inxykree, whose only contact was to perpetuate their species.