Denkiunagin

Denkiunagin appeared in 1990 TV series called Chikyuu Sentai Fiveman. Denkiunagin (デンキウナギン Denkiunagin) (12) is the eel-theme Silver Imperial Army Monster of the Silver Imperial Army Zone. Denkiunagin is sent by Billion to crush Fiveman, using its "electric giant" abilities initially to draw out the team via FiveRobo and have them attack it, only for the mecha to be easily crushed due to it being made of an electric mass. When Fiveman tries to attack the actual body with the Brother Attack, it shows resilience against all of their abilities, defeating them. However when Arthur G6 decides to help in fighting against the Galactic Warrior, the robot releases an attack that hurts it and forces it to attack leading to the robot being sent flying away to a junkyard without memory of the Hoshikawa siblings.

Seeing Arthur as the only means that could stand against Denkiunagin, the warrior and Billion attack Fiveman once again, striking it and releasing another electric giant in hopes to stop them before the robot can regain its memories. Once it does, it likewise realizes blueprints within itself that can help the team greatly. With the help of a boy who took in the Hoshikawa robot during its time without its memory, Arthur activates a transformation into the Earth Cannon, with enough firepower that finally destroy Denkiunagin and likewise eliminates the electric giant clone.

Arsenals
Its physical body is resilient and resistant to attacks, particularly against the Fiveman's weapons, as well as it can emit a high voltage of electricity from a tendril it uses like a whip. It can also release a mass of electricity and give it actual physical form, using it as a giant that can be used to attack and drain the power of FiveRobo.