Quick recap
Over three episodes, the Autobots and Decepticons reach the planet Nebulos and bond with the Nebulans: some become the robots' heads, the Headmasters, and others become weapons, the Targetmasters. Lord Zarak becomes Scorponok's partner, and Spike ends up operating the giant Fortress Maximus. The fight centers on the Plasma Energy Chamber, which could recharge Cybertron. In the end, Spike and the Nebulans shut down the chamber, and Vector Sigma routes the excess energy into Cybertron's capacitors, bringing the planet back to life. Fortress Maximus battles Scorponok, who flees with the Decepticons. In the last scene, Galvatron and Zarak bicker over who's in charge, and Galvatron vows to conquer the galaxy. Cybertron enters a new golden age under Optimus Prime, and the American series ends here.