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In "The Sleeping Sand", a paralogue exclusive to the Verdant Wind (Claude's) route, Claude travels to the Sreng region to investigate a legend about Macuil's treasure. There, the army fights The Wind Caller, who is Macuil himself in the form of a magic beast.
Having grown disgusted by humanity, he refuses to interfere with the ongoing war even after learning that Seiros is in danger from Seteth (who is Cichol in disguise). He bears great hostility towards Claude for being a descendant of the Ten Elites, and is less than friendly towards Byleth for carrying the "stink of Sothis." Whether he dislikes Sothis herself, or thinks Byleth is a descendant of Nemesis, the one who consumed Sothis' blood and gained her Crest of Flames, is not completely clear.
Following the battle, he falls asleep. Claude takes the Sword of Begalta from him as his reward.