Galvatron (Generation One)

Galvatron was the reconstructed version of Megatron, and the main antagonist of The Transformers: The Movie, and Season 3 of the Generation One cartoon.

The Movie
In 2005, after being mortally wounded by Optimus Prime, Megatron was left to float aimlessly through space after being punted out of the overloaded Astrotrain by Starscream, who took command. Drifting aimlessly, he was summoned by Unicron, who ordered him to destroy the Matrix. Megatron was offered a new body, a warship and new troops to command, so long as he destroyed the Autobot Matrix of Leadership. At first, Megatron agreed and was reformatted into Galvatron, a new, powerful fighter. Unicron then reformatted Galvatron's troops into Cyclonus, Scourge and the Sweeps.

Travelling first to Cybertron, Galvatron quickly retook command of the Decepticons after killing Starscream in the middle of his coronation. He then went to Earth and attacked Autobot City full-force. Ultra Magnus led him away from Earth, and Galvatron chased him to the Planet of Junk, where he defeated Magnus and took the Matrix, intending to use it against Unicron. Galvatron could not open the Matrix, and as punishment for his treachery, Unicron swallowed him whole. Inside Unicron, he met up with Hot Rod. Though he initially suggested an alliance with the young Autobot against the mutual threat of his master, the Chaos Bringer mentally tortured Galvatron for his attempted treachery and then forced him to attack Hot Rod. Hot Rod eventually managed to wrest the Matrix away from Galvatron and open it, transforming him into Rodimus Prime, who hurled Galvatron into deep space.

Season 3
In Five Faces of Darkness, Cyclonus, Scourge and the Decepticons, who were reclocated on Charr, sought out Galvatron. They found him sunk in a lava pit on the planet Thrull and managed to free him. However, the effects of the "plasma bath" irrevocably altered Galvatron's sanity, rendering him omnicidally insane. Upon regaining his freedom, he thrashed Cyclonus and Scourge and blew up Thrull.

Galvatron led the Decepticons on many adventures against the Autobots throughout 2006, though his insanity would usually lead to each mission ending in failure. By the time of Webworld, his derangement became so severe,Cyclonus was left little choice but to dupe Galvatron into taking therapy sessions on Torkulon. After nearly murdering an attendant during a word-association session and somehow building a gun in arts and crafts, Galvatron was deemed incurable by conventional methods. The doctors attempted to use living extensions of the planet to give him a lobotomy, but Galvatron broke free and murdered the sentient organic core of Torkulon. After that, he razed the entire planet's civilization, leaving them so broken it would take centuries to rebuild.

However, despite his insanity, he teamed up with the resurrected Optimus to stop the Hate Plague in The Return of Optimus Prime. Galvatron wound up becoming infected by the plague and attempted to kill an unconscious Optimus Prime with a axe. Optimus woke up in the nick of time and opened the Matrix directly in Galvatron's face. The wisdom of the Matrix not only cured the universe of the Hate Plague, it cured Galvatron's madness as well. Grateful, Galvatron lucidly declared a brief truce.

Season 4
In The Rebirth, Galvatron called off the truce and led an assault on Autobot City, searching for the Key to the Plasma Energy Chamber. Having converted Cybertron into a galactic dreadnought, Galvatron maneuvered it into Earth's orbit, planning to release the Plasma Energy Chamber's payload into Earth's sun. The resulting supernova would wipe both Earth and Cybertron off the face of the galaxy, presumably leaving Galvatron to gain mastery over everything left. Grudgingly teamed with the Transformer-Nebulan hybrid Lord Zarak, Galvatron was eventually defeated and sent tumbling through space, ushering Cybertron into a new Golden Age. After regaining control, Galvatron vowed to collect energy from disparate corners of the galaxy and return to Cybertron. Zarak made it clear he intended it to be a "we" leadership.