Wisdom Gu

Wisdom Gu is a legendary wisdom path Gu first introduced through The Legends of Ren Zu. Its light accelerates thought and deduction, but proximity consumes lifespan unless the user has a way to avoid that cost. Fang Yuan exploits the light without refining the wild Gu, using it to solve recipes and killer-move problems beyond his unaided capacity. (Chapters 5, 722, and 1073)

Ownership and later state

Because the wild Gu is not refined, borrowing its light differs from commanding a personal Gu. Rank-nine venerables are presented as capable of refining and directly using it, and Star Constellation Immortal Venerable historically spent great effort contesting its will. (Chapter 1557)

The Wisdom Gu central to Fang Yuan's earlier deductions is destroyed during the fate war. A later rank-eight Wisdom Gu is nevertheless available and remains useful to him, so references after the war concern a distinct later state rather than an unchanged survival of the original. (Chapters 1962–1966 and 2307)