Battlestars: Return of Convoy

With his transformation into Galvatron, Megatron departed from the animated continuity, until five years later, in the Japanese-exclusive storyline, Battlestars: The Return of Convoy, which, although not animated itself (told instead through one chapter of manga and colour magazine spreads), continues the tale of the cartoon universe. In the previous Japanese-exclusive animated series, Headmasters, Galvatron had been apparently destroyed when he was buried on an iceberg. In the Return of Convoy storyline, a new evil force named Dark Nova recovers Galvatron's body, and restores him to life as Super Megatron, pitting him against Star Convoy (the reborn Optimus Prime) and his Autobots. Super Megatron subsequently gets an upgrade to Ultra Megatron, and for the final battle, merges with Dark Nova himself, becoming Star Giant.