The addition of Rsie was not that shocking. Walker knew she had been more reclusive due to her weakened state but now she was much more than just strong. It appeared that the new viewpoints of light mana that she had managed to obtain were strong enough to make a greater effect on her entire body.
The white scales on her dragonkin form seemed to have an iridescent light around them. Just enough to make it clear that a denser light mana flowed through them while also showing off the pristine purity that was within the light mana in Rise's body.
Just purifying the light mana that she absorbed and used overall was a major step that changed the strength she had overall. It meant that she would be able to use less of her own mana to be able to alter the light mana around her. On top of that, it had been able to help her grow as a dragon.