Ace didn't know that his action of refining the materials with Chuchu's spirit fire had just revealed something extraordinary about Chuchu to the two outer sect elders, as he was fully focused on the forging.
He could do without it, but then he knew he wouldn't be able to forge a grade-9 treasure because using a spirit fire raised the chances of the final product tremendously, whether it was in alchemy or forging; even the rune crafting was the same.
Furthermore, he had another reason to use Chuchu's spirit fire: He wanted to hide the extraordinary properties of his Holy Twilight Qi, which he upgraded with his avatar and called the Holy Twilight Spirit Qi.
It shocked even him when it happened while he was still in the thief's house.
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-Cost of Cultivating the Avatar of Holy Twilight to Law State with Prime Law: Holy Twilight: 100,000,000 Thief Points
