This refers to the Incense stick that Bai Xiaochuns parents gave him before they passed away.[1]
Origin[]
Supposedly, is was passed down by Bai Xiaochuns ancestors by a down-and-out Immortal who they had saved. The Immortal gave them this incense stck before his departure as a sign of gratitude. He promised to take a member of the Bai Clan as a disciple and that he merely had to burn the incense stick and it would summon him to their side.
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