Earth

Earth is a location in G1 for one reason that the show states plainly in its first episode: it is rich in the energy Cybertron has run out of. The Ark came looking for fuel, found this planet by accident, and four million years later both crews woke up on it. Teletraan I scanned the local traffic and rebuilt every Transformer aboard as an Earth vehicle, which is the single production decision the entire toy line rests on. From that point the Decepticons' project is straightforward strip-mining: convert oil, electricity, geothermal heat, solar power and anything else into energon cubes and ship them home.

The humans are participants rather than scenery. Sparkplug Witwicky and his son Spike become Autobot allies in the pilot, Chip Chase provides the technical support, and Daniel Witwicky carries the role into 2005. On the other side Doctor Arkeville collaborates with Megatron on the hypno-chip and the space bridge. Earth's governments are largely absent from the cartoon, which is one of its stranger omissions, though Marvel UK later has them co-fund Autobot City.

Earth is also repeatedly nearly destroyed. Megatron pulls Cybertron into its orbit in The Ultimate Doom, wrecking its weather and tides to harvest the resulting disasters. Onslaught tries to push it into the sun in The Revenge of Bruticus. Megatron attempts to convert its organic matter into dead metal with the Key to Vector Sigma. Galvatron tries to make its sun go supernova in The Rebirth. For a planet the Transformers landed on by accident, it takes an extraordinary amount of punishment.

• Earth's role is entirely commercial in origin: the Transformers become cars and jets because a crashed alien ship needed a reason to scan Earth vehicles.
• The cartoon almost never involves Earth's governments or militaries, which is a notable difference from the Marvel comic.
• Earth's energy is the war's actual objective for the whole of seasons one and two; every Decepticon plan is fundamentally a resource-extraction scheme.
• By 2005 Earth is the Autobots' home rather than their exile, which is why losing Autobot City in the film hits as hard as it does.