The Last Damning of Remnant (or: How 2 OP idiots screwed the plot)

This is a shameless multi-SI, OP OC Gamer fic. Do not read if you hate these.
Alexander and Jonny die in nuclear hellfire and are sent to purgatory, where the oversoul sends them to Remnant for shits and giggles. They don't get a choice in what powers they want... so what do they get...? well, dear reader, whatever it is, it will ruin Remnant's plot forever just by virtue of existing within it!

Obvious plot divergences at some points. Plot changes, lore expansion, shameless use of fanon and headcannon. CONVERGENCE of multiple universes!