Duality.
Damien always practiced with duality in mind.
He never leaned too far to one side, because his path was one close to nature. Just like everything in the natural world had an equal and opposite, his laws were the same.
Duality was an extremely important concept, not just to Damien, but in general, but it wasn't a concept that could be comprehended.
It was an overarching truth on a completely different level than other concepts. Therefore, while Damien always kept it in mind, he was never able to harness the power of duality properly.
But if he could…
He knew it would create something amazing.
For this move, he separated his laws and abilities into two equal and opposite parts. When he used everything he had, from Existence to the Void, to ease the tension between both sides and bring them together…
VOOOOOOOOM!
A massive pulse of mana spread through the sky, bringing light to the dark world.