The King of Braves GaoGaiGar: Mikoto Utsugi (Episode 48)

This is right after Gutsy Galaxy Guard's (G3's) epic battle against the Zonder Master at Jupiter and they were on their way home with a few survivors, Mikoto was infested by a Zonder Spore thanks to Pasder's last ditch effort to stop mankind long before he was defeated which caused her to lose control of herself and started to drain the energy from all the machines and the Brave Heroes around the Orbit Base. She then reached a terminal stage, transforming her into the final ultimate threat: Zonuda. The final battle on Earth was forced to be deeply personal, pitting Gai Shishioh against the person he loves most in order to save the world again but willingly to sacrifice himself to save her.

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