Kyoushoku Soukou Guyver (1989)

When high schooler Sho Fukamachi stumbles upon a mysterious, biomechanical relic, his life irrevocably changes. This strange device, known as the Guyver unit, forcibly bonds with him, transforming him into a formidable, armored super-soldier. Unbeknownst to Sho, this newfound power thrusts him into a clandestine war against the Chronos Corporation, a shadowy organization that manufactures monstrous, genetically engineered creatures called Zoanoids and seeks to reclaim the Guyver for their own sinister agenda. Now, Sho must navigate the terrifying reality of his altered existence, battling grotesque horrors and confronting the truth behind the Guyver's origins, which may be far more ancient and alien than he could ever imagine. As the line blurs between human and monster, Sho fights not just for his survival, but for the fate of humanity itself against forces beyond comprehension.

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