Gu Xuanfeng tapped the storage pouch, revealing a black iron nail-like object over a foot long. Under his urge, it transformed into a black light, shooting towards Gu Yuan.
The black light was swift, and its momentum was considerable.
It carved a long black trail in the air, aiming straight at Gu Yuan's brow.
This nail was indeed somewhat special, a coffin nail refined by an evil Dao Yin Spirit.
It was a lower grade magical treasure, not considered high in grade, but even if someone were to exchange it for an upper grade magical treasure, Gu Xuanfeng would never agree.
Because, during its refinement, part of the corpse of a powerful Yang Spirit was integrated into it, containing a terrifying corpse poison.
Let alone a Golden Core Great Cultivator like Gu Yuan, even if a Yin God Giant were to come, they would die miserably on the spot if struck by it!
He initially planned to use other means to defeat Gu Yuan, but now such calculations were clearly out of question.
