The fixed canon anchors are that Cyrion is a Nostraman veteran of First Claw, possesses a psychic ability linked to sensing and tasting fear, visibly ages under its influence, supports Talos after Vandred’s fall, carries the bolter Banshee, and receives an augmetic arm after being maimed during First Claw’s conflict with Vraal. His hidden predation is eventually uncovered by Uzas, whom Cyrion attacks and successfully frames before Talos; he later dies on Tsagualsa during Jain Zar’s destruction of First Claw.

I’ve placed his default timeline aboard the Echo of Damnation, before Tsagualsa.