Freeza

Freeza, was the true first villan the Z warriors had to encounter. (Yes they did fight Vegita first, but Vegita later sides with the Z warriors) Freeza was the being known for destroying the saiyans' home planet, Planet Vegita. Freeza was considered the most powerful being in the universe and even Kaio-sama believed no one could defeat him. The battle with Freeza was long and intense, spawnning into about 6 mangas (or 80 or so episodes). The Z warriors had a hard time with Freeza and after numberous attempts, Freeza kept overpowring them. The battle finally turned when Son Goku came. Despite Goku's efforts, Freeza still held his own untill Goku turned SSJ. Eventually, Freeza became no match for Goku and was destroyed when the planet Namek was blown up. However, Freeza was recreated by his father, King Cold, But they were both eventually destroyed by the sword of Trunks. Freeza was a powerful villan and had to power to transform his body into 3 forms, each increaing his power level by millons. His one ki Blast could kill a person on impact as it did so with Dende and Vegita.

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