In Dheion's dimension, Dheion fires a beam of energy with so much force, that everything in its path is obliterated. Power tries to block the beam with his indestructible Hylian Shield, but even the Hylian Shield can't take the force of the beam, quickly disintegrating. Power switches to his Frozen Phoenix Form which gives him godlike durability and makes a god-ice shield, but even that can't stop the beam. Power does have one more trick, though. He starts glowing as bright as the sun, blasting straight through the beam at the speed of light and impaling Dheion on his Claymore of Light. Power entered his Golden Phoenix Mode.

https://preview.redd.it/9cu53vlnxghd1.jpg?width=1024&format=pjpg&auto=webp&s=f1d8fc09b793364a2e685d5b8055595d67d8d8b2

Dheion: What... is this power?

Power: This is when I become one with Chrysonikas. Remember Chrysonikas? That omnipotent being you created when you granted my wish?

Dheion: Even with that you don't stand a chance!

Dheion kicks power away before they both clash their weapons with so much force, that the galaxy around them (still in Dheion's own dimension) is destroyed. The two zoom around past the speed of light, clashing weapons with the forces of actual supernovas. After a few seconds, Dheion somehow manages to impale Power on his staff.

Dheion: Even with that power boost, you couldn't stop me. I'll destroy that dimension you were trying to protect. Then, I'll destroy your home dimension and everything you love.

Power: No... you... won't. When... when I enter this form, my... my power becomes too much for my body, so after enough time... the energy is released, destroying everything...

Dheion: NO!!!

Back in regular Hyrule, a giant explosion happens in Hyrule's sky, as big as a nuke. The energy released was so great, it destroyed Dheion's dimension AND barely broke the barrier between the dimensions making a tiny fraction of the explosion happen in regular Hyrule. Both Power and Dheion are gone.