Not sure exactly how you arrive at sullied backstory. Little of it really deviated from the game. We already knew they "rebelled" vs their masters to end the Mandalorian threat. What was never specifically covered in the game was what exactly happened in the period between the end of the Mando Wars and the Jedi civil war. Seems that contact with the Star Forge and maps changed the motivation from betraying the Republic to their having visions of creating a force to rival their newer sith master. When Kreia speaks of a betrayer, she could apparently be talking about Revan as well as anyone else. He betrayed his Jedi masters to fight the Mandalorians, betrayed the Republic for the "true Sith" and then betrayed his new master for his own ambitions and finally his own forces in his "redemption".
But hell, even if you figure they ruined Revan, look what they did to Vader w/the PT. Still surprised?
Now, I want you to remember that no bastard ever won a war by dying for his country. He won it by making the other poor, dumb bastard die for his country.---Patton
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