To surpass twilight and become an elder dragon, Luminous had to discover the full scope of light and all of its wavelengths. She had managed to see far past the visible light and extended her dominion even to the radiowaves and microwaves.
With her light, Luminous could outshine a star, and her mere existence was a hazard to all living beings. The fact that she had managed to tame her own light down to the point she is just blindingly bright was a miracle.
Time, Light, Void, and Mana dragons were all magic dragons, on the same level of power. If an Elder Void dragon could carry entire solar systems into war, it also made sense that Light dragons would be on the same scale of power.
But that was her problem as well; she couldn't unleash such powerful light here in the mortal world without frying it. To win this fight, they needed either something precise or to get Nyar out of the universe where they can blast him.
