I've seen it might have something to do with Dead Orbit but even then people don't seem to be at a concensous on that.
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Edited by slackerboi: 11/19/2014 4:49:49 AMOnce you complete the hard mode raid a certain amount of times, a nightfall option will appear and you will be able to earn "chatterblack" after defeating Atheon. [spoiler] not really, but a super black shader exist, I'm pretty sure. I think I've seen people in a shader like that.