Arvis is an antagonist in Fire Emblem: Seisen no Keifu. He is one of Cigyun's children, and because of this lineage, he plays an important role in Manfroy's schemes. After Manfroy abducts and brainwashes Sigurd's wife Deirdre, he allows Arvis to find her and fall in love.
After taking Deirdre for himself, Arvis eventually betrays Sigurd, leading to the deaths of Sigurd and many of his allies. He also fathers twins with Deirdre; Julius and Julia, who play further into Manfroy's plot. Arvis eventually meets his end in battle with Seliph, son of Sigurd and Deirdre.