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After securing the Black Crystal Finger Bone, Ange felt a bit lost. How should he use it? He looked up at Leixinna for guidance.
When Leixinna poured her spiritual power into the golden egg, he followed suit, and then suddenly the whole world became clearer to him.
There are two ways Undead perceive the world: passive and active sensing. The limit of soul extension defines the boundary, with closer being active perception, and farther being passive perception.
For example, if a soul can extend beyond a wall a few meters away, one can actively perceive and see what's happening on the other side; but if the wall is several kilometers away, since the soul can't reach that far, one cannot see and thus only has passive perception.
Passive sensing, for instance, can detect things like the sun, stars, and clouds that emit vibrations, even at great distances. However, a floating stone in the void would go unnoticed because it emits no vibrations.