He's betrayed the Veil and the Dead beyond
"You don't know his name, it is long since forgotten, but he is Mataurin; warrior, magi, and once advisor to the council. He would not leave when the earth screamed and split our city in the night, I know now he saw it as his chance to rule. So he remained, along with those he could convince, and those that were his thralls. But his magic wasn't powerful enough to stop nature..." the one time merc shakes his head.
"Mataurin must be dealt with, and then we all can rest." All the voices mumble in a chorus. "And yes there were others, but they have become like me. Beware the night, Mataurin grows strong, he calls upon the memories of the ages to amuse him with things long since turned to dust; thoughts walk like ghosts, and he can command them to possess the living."
The former merc's eyes shift through a rainbow of colors once again before he settles on a new voice, stern and sharp as Zee's ready blade. "I should kill you now, or die trying, that would be a good death. The others fool themselves, there's no miraculous transcendence, not for those that have betrayed their orders and plotted death."
A deep growl escapes the merc's lips and he shakes his head. "Mataurin is already dead and so are we," the stentorian voice snarls. "He's betrayed the Veil and the Dead beyond." The merc's eyes, dark as coal, bore into Noi'nu, and he visibly shakes with tension, "Leave us to our fate, we can control ourselves, but we cannot help you. The others that entered our city will probably help you less, steel and blood will be their answer to any words."