The show tells us that the GoBots are from Gobotron, a planet that was once home to a race of humanoids, the GoBings. Thousands of years ago, a terrorist group known as the Renegades started a war with a group of peaceful people called the Guardians, which ultimately ruined their planet. OK, that sounds a lot like the Transformers’ back story so far. But here’s where shit gets weird.
Facing extinction, the survivors sought out a man known only as the Last Engineer. Not because he was the most brilliant scientist or because he had a way to fix the planet. No, they needed him because for years, he had been slowly transforming himself into a cyborg by cutting off parts of his own body and replacing them with machinery. For fun.
The GoBings decided to allow the Engineer to transplant their brains into robot bodies, allowing them to survive as GoBots. He provided these transplants indiscriminately to both sides, Renegade and Guardian alike, until they had all been assimilated.
When his work was done, the Engineer disappeared and left the two factions to continue fighting. Challenge of the GoBots is set in modern times, which means that the GoBots have been at war for thousands of years. Which is to say, this toy line is about human minds, trapped in metal bodies, trying to destroy each other. Forever.