Order of the Darksoul
Even before the great impact there were those that studied the Xintavu, just as there were those that broke through. The Order of the Darksoul were those that took to combat the few Xintavu that were able to transport themselves from the Abyss before the Great Impact, for even a solitary member of the banished race is a force to be reckoned with.
Using powerful binding magic the monks of the Order were able to gain the powers of the Xintavu in order to combat them, though the process scars their souls irreparably.
During the Great Impact the Order lead the fight against the Xintavu, resulting in the death of many of their order.It is rumoured that the Darksiders took their beginning from this nearly forgotten monastic order at some point during or after the Great Impact.