For a SR/Dark theme, my new guy's origin is he was trapped in the Netherrealm, hunted by a monster and over the course of his time there learned to be super agile and when he finally defeated the monster, he took it's dark powers.
Kinda answered it yourself there. Me, personally, I don't think anything he does is for anything other than to garner attention (usually the bad kind). He's constantly proven wrong, never relents and comes back again and again with the same "the sky is falling" drivel. To put it more succinctly: