Direct answer
Prepare items: Withered Bone ×10 Go to the location: Bonemass Put the offering on the hotbar and use it on the altar. The listed quantity is consumed. Withered Bone ×10 Summoned target: Bonemass
Withered Bone → Bonemass · Offering

Result
Prepare items: Withered Bone ×10 → Put the offering on the hotbar and use it on the altar. The listed quantity is consumed. Withered Bone ×10
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