HBTaker but Taker is God of Darkness
Basically almost Persephone x Hades trope
So basically Undertaker was no ordinary wrestler, and no ordinary man, he's a literal God of Darkness and the story was same thing as Undertaker lore, exception he found love at Shawn's past life, he's the Bringer of Light and Life. Until Paul Bearer ruins everything and that includes Shawn being killed and Kane's rising, so Undertaker probably trapped Kane somewhere so that he'd never make trouble again and Paul Bearer? Demoted as a God.
Until in 90's, Paul Bearer's descendants founded Ministry of Darkness and hoping to find Undertaker, however Undertaker just wrestles as usual and not using his powers for evil.
Until he found his beloved that resembles to his lover, however Shawn Michaels can't recount the times so he and Undertaker that time are enemies. Undertaker feels sad deep inside because poor guy his lover never remember him, but Shawn sometimes has dreams where he brought life and light for his beloved man.
Hell yea we want Hades x Persephone AU but Hades lost Persephone