This is the refinement level when one is considered a high-level genius in the universe. Any further and you would be among those who are called monsters as the further you go the harder it becomes to refine your core further and after 90% it gets so much harder that people don't waste too much time and decides to enter the next realm. Now Jiaxin has that chance. Previously her fire core was stuck at 87%. It is already great considering she wasn't using a top scripture and now with its help, she would reach that level and her wind core would also reach that level too. She would be unrivaled at her level unless she meet people like her or someone like Vishnu.