Buying My Way Through the Multiverse

In a dead world overrun by walkers, Gray gains access to a system capable of buying almost anything: weapons, skills, powers... even abilities from other universes.At first, surviving The Walking Dead seemed simple enough.Then he discovered Rebirth.A feature that allows him to travel between worlds while permanently keeping some of the powers he earned.Now, every apocalypse, every universe, and every battle is a stepping stone toward something far bigger.And Gray plans to survive them all.First time doing this, so don't expect award-winning writing.Might also mess up timelines or places but just take it as an AU :)