Autobot Spike
Sparkplug creates Autobot X out of spare parts. The robot goes crazy during its first test and is put into storage. Later, Spike gets badly injured in a firefight with the Decepticons. To save his life, the Autobots transfer his mind into Autobot X so the doctors can operate on his body. With an unstable mind and Megatron's goading, Autobot Spike turns against the Autobots, but relents when he nearly kills Sparkplug. Spike's body makes it through the operation, and Spike's mind is returned to it.