Skyfire
On Cybertron before the war, Sky Fire was a scientist and explorer working with Starscream. Together, they investigated an uncharted planet (Jacinto), where they failed to find signs of intelligent life. Sky Fire wished to scrutinize the planet further, and moving in close enough to the planet, a polar wind storm swept him up and buried him beneath the Arctic ice. Starscream searched for his friend, but was unable to locate him and returned to Cybertron alone.
Millions of years later, in 1984, the Decepticons excavated the frozen Skyfire while draining heat energy from the Earth's core and reactivated him. Reunited with his old friend, Starscream, Skyfire joined the Decepticon ranks. When the Autobots arrived, Skyfire engaged in battle with them, but then saved the Autobots' human allies Sparkplug and Spike Witwicky when they became stranded on an ice floe. Naively, he took the two to Megatron under the impression that he and the other Decepticons were good, but when Megatron took them as prisoners, Skyfire started to question his allegiance. When Starscream ordered him to destroy the captured Autobot search party, he refused, and Starscream turned his weapons on him, leaving him heavily damaged. Repaired by Ratchet, he joined the Autobot side and engaged in a dogfight with Starscream which ended when he sacrificed himself to stop the core drain, burying himself in ice once again in the process.
A short time later, however, Skyfire was recovered by Wheeljack and Sideswipe, and immediately participated in an attack on the Decepticons in Peru, where the antagonists were once again attempting to use the Earth's core energy for their own means. Skyfire was almost permitted to destroy the villains' new weapon by Thundercracker, but was then blasted by Starscream and repaired with some difficulty by Spike.
Skyfire would go on to make semi-regular appearances in the immediate future, helping the Autobots evacuate their base when the volcano it was embedded in became active, and flying a squad of troops to battle the Insecticons.