Bankizoku Gaiarc (Savage Machine Family/Clan Gaiarc) The Gaiarc come from the Machine World and their main aim is to pollute the Earth. The machine family is made of three main members. The Gaiarc based themselves in a fortress called the Hellgaille Palace on an isolated island.

Ground Assault Minister Yogostein Yogostein is in charge of polluting the Earth, he is the leader of the three. He is armed with a spear. He might look gruff and tough, but in actuality, he as flappable and as susceptible to overestimating his success as the other ministers. He is not over using his subordinates to his advantage. He ends his sentences with "Nari." He revels in the success of his subordinate Hiramechimedes and admires and beleives in him very much.

Aerial Assault Minister Kitaneidas Kitaneidas enjoys polluting the skies and atmosphere. He wields a staff. He ends his sentences with "Zoyo." He experimented with Bikkurium's potent abilities prior to using it on Barbaric Machine Beasts.

Aquatic Assault Minister Kegalesia Kegalesia's main concern is polluting bodies of water. A whip is her weapon. When she steams up, her comrades can turn it off by turning her valve on her helmet. In Episode 4, she is the first to face the Go-Ongers and it is discovered she is machinery underneath, meaning she is an android. She can also quickly heal. She ends her sentences with "Ojaru", is a heavy drinker, and hates to be called "Old Lady". In Episode 14, she donned the guise of Rena Kegareshi to figure out the secret of a dojo owner who bested one of her minions and Hanto falls in love with her and calls her beautiful and pure, which is offensive to her, so she develops a vendetta towards him.

Barbaric Machine Soldiers Ugatz Gaiarc's android grunts fight the Go-Onger and pilot the Gaiarc mecha.

Barbaric Dohma The Gaiarc's mecha that the Ugatz and the ministers pilot. They are capable of leaping in the air like frogs or to actually fly in the air.

Barbaric Dohma SP The personal jet fighter of Hiramechimedes is a Dohma that looks more like a Mantis. Each able to hold up to four Barbaric Dohma on itself to resemble a classic WW1 airplane.

Land Pollution Vice-Minister Hiramechimedes He is Yogostein's partner who Yogostein admires and is the best tactical intelligence of Gaiarc. He is a genius and whenever inspired with a plan, the three lights on his head flash. In spite of his lower ranking, Hiramechimedes is feared by the Engines, his victories against them making frightened husks of their former selves in his presence. However, on the day the Gaiarc were expelled from Machine World, Hiramechimedes mysteriously disappeared during the fight only to resurface months later on the Human World. According to him, when the trio left, the Wing Engines suddenly appeared and sent him running to the Human World. He has a special class of screws that can strengthen the Ugatz. With his sword and blinding speed, he can perform Equilateral Triangle Slash and Isosceles Right Triangle Slash. He is good at geometry when it comes to his attacks. A running gag with Hiramechimedes is that the Go-ongers, besides Renn, mispronounce his name.