"...Call me Doppleganger..." was the only answer, it had turned amused as he backed into the shadows... "Or call me an unanswered question... its up to you. "But for now... you can call me... gone."

And as he vanished fully into the shadows, he simply was. Rifted, teleported, transported, spirited away it was hard to say.
The end result was only that he was gone, and not a single answer to be found.