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Artifacts in Anime Origins are not equipment you wear — they are portal keys. Each artifact has a grade (Intact, Empowered, Perfected, Ascendant) and opening it sends you into a special portal run for its own drop pool. You get them from Legend Stages: Karakura Town Legend 1 drops KTR-1, and Hidden Sand Legend 1, 2 and 3 drop SND-1 through SND-4. Umbral Splinters, earned from the same clears, are spent at Robyn [Artifacts] to refine an artifact into a higher grade, which raises its signature drop chance. The materials you pull out are what craft Starku (Resurrected) and the Ghost's Gunbai.