Earth
The planet Earth, third from its sun in the Sol System in the Milky Way galaxy, is a world populated by a wide variety of native organic lifeforms, most notably, humans. Versions of this planet are known to exist in many dimensions within the multiverse, and it frequently becomes involved in the conflicts of the Transformers.
Generation 1
U.S. Animated Continuity
Around nine million years BC, the Earth was visited by the Transformers Starscream and Skyfire, but Skyfire was caught in a polar wind storm and separated from Starscream, buried in ice. Then, four million years BC, the Transformers' spacecraft, the Ark, crash-landed in what would become the north-western United States, entombing the robots within in stasis.
Earth is home to many unusual creatures and "hidden civilisations." The underwater city of Sub-Atlantica, populated by water-breathing fish-like humanoids, gave rise to the legends of Atlantis and other sunken cities. Also, fire-breathing dragons exist naturally as late as the medieval era, though by the 20th century, they appeared to have died out. A possible descendant was the unique, reptillian creatre known as the "Beast of Borneo" captured by big game hunter Lord Chumley.
The magma energy of the Earth's core is channeled by a series of green crystalline structures, which the Decepticons attempted to exploit in 1984, exposing a crystal shaft in the North Pole and tapping the core's energy (while, at the same time, happening upon and reactivating the body of Skyfire). Another unusual aspect of the planet is the natural existence of electrum, a metallic alloy that renders Transformers invulnerable when coated in it.
By the year 2005, human interaction with the Transformers had resulted in an advanced level of technology worldwide, and the foundation of the Earth Defense Command, which operates a series of space stations. Saturn's moon, Titan, was colonised, and an EDC base was established on Mars, while travel between star systems was hugely enhanced by the creation of warp-gates. Earthling Spike Witwicky became Earth's ambassador, first to Cybertron, and then to other alien worlds as, through the Transformers, humanity came into contact with other races.
Japanese Animated Continuity
In the expanded fiction of the additional Japanese-exclusive animated series, the existence of the sunken continents Atlantis and Lemuria was confirmed. Later, it was revealed that a small group of Autobot and Decepticon Pretenders crash-landed on the planet in the Stone Age. While the Autobots used their Pretender abilities to adopt the form of humans, the Decepticons assumed monstrous forms and were mistaken by early man as "demons." Finally defeating the Decepticons and sealing them away - within the pyramids of Giza, the ruins of Atlantis and beneath the Nazca Lines of Peru - the Autobots then integrated themselves into human society, serving as secret protectors who quietly and subtly guided the evolution of human society.
Marvel Comics Continuity
Dreamwave Comics Continuity
IDW Comics Continuity
Beast Era
Beast Wars
The mysterious alies known as the Vok chose prehistoric Earth as the site of an experiment, and seeded the planet with vast amounts of raw Energon, installing a second, artificial moon into the planet's orbit and placing several devices at strategic points on the planet. Around the time of the emergence of proto-hominids, a group of Maximals and Predacons from Cybertron's future travelled back in time to prehistoric Earth, where they waged a war they dubbed the "Beast Wars," and encountered the Vok, interfering in their plans. Deciding that the Beast Warriors had contaminated their experiment, the Vok activated the second moon, transforming it into a giant laser weapon with which they planned to detonate the Energon seeded throughout the planet, wiping it clean of life. This plan was foiled by the Maximal leader, Optimus Primal, but the vast majority of the raw Energon on the planet was transformed into stable, cube form. Eventually, the Maximals returned to Cybertron with the Predacon leader, Megatron their prisoner. The only surviving Preadacon, Waspinator, was left on the planet as the leader of a tribe of protohumans. Although they eventually rejected him and he too returned to Cybertron, it is unclear precisely how much influence Waspinator may have had on the evolution of humanity and their culture.
Beast Wars II
A future version of Earth was later visited by Maximals and Predacons under the command of Lio Convoy and Galvatron, respectively. At first known only as "Gaia," the world was known to have two sentient inhabitants, a girl named Artemis and her companion Moon. Although the prescene of what seemed to be a decimated Tokyo Tower suggested that Gaia was Earth, it was not fully confirmed until release of the Robot Masters toyline's version of Lio Convoy, the bio to which reavealed that Earth had been devastated by mankind's tampering with the power source known as Angolmois energy.
