|Voiced by|| Nobuo Tobita (Japanese)|
Chris Patton (Funimation)
Viper and his family are considered enemies of Keronians.
Viper appears recurringly in the series.
In episode 121, he returns as Mecha-Viper and pretends to be Dororo as he approaches Chiroro and Karara. His body was half mechanical at the time; which resulted from the damage the Keroro Platoon has inflicted on him last time.
In the manga, Viper has a more repetitive role. After his defeat at the hands of Keroro and his Platoon, Viper was attacked by Alisa Southerncross. Angered by his second defeat, Viper finds out about Alisa from a police report. Eager to enact his revenge, Viper enlists the assistance of an alien called a Chupacabra. He finds Alisa and kidnaps Fuyuki to force her to fight, but during the battle, Alisa was weakened, and the Chupacabra lunged in to eat her. But before it could, the Keroro Platoon appeared again to stop it and Viper altogether.[cite this]
After a few issues[cite this], Viper returns as a cyborg named Mecha-Viper, with the intention of getting back at the Platoon for his past failures. But his new form was wasted for nothing, as the Platoon was currently busy, and had no time to fight Mecha-Viper.
The first Viper who fights the Keroro Platoon because of a war between the Keronians and the Vipers, and was defeated by a technique used by Dororo. He reappears in Episode 121, where he appears as a cyborg who takes revenge on Dororo, but ends up capturing Chiroro and hides in Alien Street from the Space Police and the Keroro Plantoon. To keep himself from being spotted, he disguises himself as a chef in a ramen stand. When Keroro disguises himself as Viper and captures Karara in an effort to earn money, Viper takes off his disguise and attempts to defeat the fake Viper, proving that he does have some good in him. Viper's cyborg appearance is very reminiscent of Frieza, of Dragonball Z fame, when he became Mecha Frieza. His left half has been completely demolished and replaced with mechanical parts, his left eye is green and has a yellow scope as its pupil, a black tube appears on his head and leads to the back of his head, and the buster arm he had before has now been replaced with a mechanical claw. He has a son that was taken away by his ex-wife who he taught a technique on how to make the Tokyo Tower out of cherry stems.