The Garbans are led by Belzeus, who is also a member of the Warp Monarch's highest council. Several Garbans were members of Belzeus' conspiracy to gain control of the Earth and use it as foothold for his intergalactic conquest.
The first Garban to appear onscreen was Brighton, who visited the Earth during the three-day ceasefire between the Earth and Warp Monarch. Brighton claimed to have come to Earth to locate the descendant of the Bosquito, but this was just a cover for his true goal, finding the Communicator to prevent her from contacting the Warp Monarch's Will and informing it that humanity was not descended from the Bosquito.
Belzeus' next move was to send out Gorgion to kill Ruby before she could awaken Ran's powers as the Communicator. Gorgion summoned Cabyron to hold off the Gransazers while he tracked down Ruby. Gorgion succeeded in mission, but at cost of his own life, as he wound up having to suicide bomb Ruby, taking both him and her down.
Cabyron continued to battle the Gransazers as Belzeus arrived on Earth's surface to kill with Ran. However, Ran was able to awaken her Communicator powers and make contact with the Warp Monarch's Will, prompting the Warp Monarch to call off their attack. The Gransazers then formed DaiSazer to destroy both Cabyron and the Garban mothership. Logia then took Belzeus into custody to face judgment from the Warp Monarch Council.