Yang Jing sat cross-legged before the Celestial Spirit Eight Trigrams Furnace, manipulating the Five Elements True Fire to refine the Magical Treasure.
The Celestial Spirit Eight Trigrams Furnace also contained a Spiritual Fire called the Wuding Divine Fire, a Tier Four Spiritual Fire used specifically for Artifact Refining.
However, Yang Jing was accustomed to using the Five Elements True Fire for Artifact Refining. Even with the more effective Wuding Divine Fire available, he stuck to his old habit.
As a Magical Treasure the Ruan Family had exhausted their clan's fortune to refine, the Grand Thousand Mirror had even been made with several types of Tier Five Spiritual Materials. Furthermore, a Ruan Family Nascent Soul Cultivator had nourished it for ten thousand years, giving it an incredibly solid foundation.
