Zambot 3, along with the King Beal, are the primary defenses against the Gaizok invasion. Zambot 3 is formed when the Zambird, Zambull and Zambase combine by a sequence called Zambot Combination. There is a separate cockpit for each pilot. In the final battle, the Zambull and Zambase are destroyed in Uchūta and Keiko's successful suicide attack, and the Zambo Ace is damaged beyond repair.

Zambot 3 would continue to fight until the war's final battle at Bardos Island. There, the legendary King Ghidorah was awakened, taking out a large amount of the army's mechs and heavily damaging the rest, including Zambot. Seeing no other option, all three performed a suicide attack to puncture through his defenses. Sad to say, none of them survived, but their strategy did work, with the Zambot's destruction managing to weaken their opponent severely, making an opening for the rest of the ARC crew to take him out. Their sacrifice had a profound effect on their comrades, especially Akira, who abandoned Raideen and secluded himself from the rest of the world, finding a place to settle in a far-off cottage.