The green smoke drifted and coalesced in midair, finally forming the shape of an arrowhead.
The arrow pointed in one direction before vanishing.
Seeing Shen Bai staring intently, Elder Mu explained, "Yin Incense. It's made by roasting with Corpse Oil and can be used to locate Yin Posts."
"Corpse Oil? That doesn't sound like a good thing," Shen Bai remarked.
Elder Mu shook his head. "Legitimate Yin Walkers buy it with their own money. It's considered a normal transaction—a willing buyer and a willing seller, after all."
Shen Bai asked, "And the illegitimate ones?"
Elder Mu chuckled. "The illegitimate ones have long been registered by the Observatory. We take them down the moment we get a chance."
"The Yin Incense can find the most suitable location for a Yin Post. Just watch. Consider it a learning experience."
Shen Bai nodded and fell silent.
