When the Great Sun Celestial Furnace Sword was refined, an overemphasis on its killing power led to an excessive infusion of Great Sun Celestial Fire.
This made its power far greater than most Tier Three Flying Swords, but it came with a fatal flaw.
Great Sun Celestial Fire would constantly emanate from the sword's body, searing its wielder on two levels: their physical body and their Divine Sense.
Imagine the highest reaches of the sky, the exclusive domain of Cultivators at the Nascent Soul Realm and above. A Core Formation True Man could only survive there briefly, and only with the help of specific Magical Treasures.
If one came into direct contact with the Great Sun Celestial Fire, a Perfect Core Formation Cultivator specializing in Body Refining could probably withstand the extreme temperatures.
Of course, it was hard to say if such a Body Refining Cultivator even existed among Sword Cultivators.
