The world of Probitas had an ancient tradition, maintained for untold millennia after its original settlers left Terra, a meditative practice that was said to unlock hidden powers latent within every person. It was said that if one could empty the self of all fears and emotion, a strange "light" would radiate from within the self, and by channeling that could one become more than human. Probitas was an agri-world, under the jurisdiction and governance of the Lord of Macragge, Chapter Master of the Ultramarines. Yearly calls for fighting men would be sent to every tribe by an unknown method to the natives: a large being resembling an armored God would visit and from his strange helmet would an authoritative voice announce the challenge.
Sextus was practicing the forms of fighting with a quarterstaff when he heard the announcement from a training ground outside the main ring of houses. He was now old enough to fight in the sight of these Godlike beings. Unlike anyone he knew, Sextus was able to empty himself and grasp the strange power his people spoke of with a reverent tone. Beyond enhancing his senses, he had not found another use for it as of yet, but the elders implied that much could be done with it.