Subaru B, designated Subaru Beyond, is a mutant duplicate of Subaru Ichinose engineered by the Metus civilization. This entity awakens as a secondary consciousness during life-threatening crises, forcibly seizing control while proclaiming divine supremacy. Contrasting the original’s demeanor, Subaru B embodies grandiosity and emotional detachment, rejecting mortal conventions to declare himself a god.

Physically mirroring his progenitor’s adult build, Subaru B is marked by stark white neck-length hair and piercing violet eyes. His consciousness is bound to the Hades Durandal—an incomplete colossal war machine engineered for high-stakes combat, which he commands as its sole pilot. Subaru B’s emergence coincides with the original’s mortal peril, implying a survival protocol fused with Metus genetic or technological tampering.

Subaru B maintains an antagonistic rivalry with Subaru Ichinose, dismissing him as an inferior predecessor. Their dynamic embodies clashing identities and existential strife, though their confrontations and potential resolutions remain unexplored in documented narratives.