Shockwave

When Megatron prepared to lead his troops in pursuit of Optimus Prime and the Ark, Shockwave was instructed to stay behind and guard Cybertron in Megatron’s absence. Swearing that Cybertron would remain as Megatron left it, Shockwave performed his duty to the letter for four million years, after Megatron and the other Transformers were entombed in stasis on Earth.

So accurately did Shockwave carry out his task, however, that no advances were achieved in the war, and the deadlock slowly caused what little supplies of energy the planet had to dwindle. In the Earth year 1984, Shockwave again attempted to make contact with the lost Megatron - only this time, he got a reply. The Transformers on Earth had been awakened, and immediately, Shockwave and Megatron co-created the spacebridge, an inter-galactic transport system, with which to send energon cubes made from Earth’s energy to the depleted planet. In the first tests of the spacebridge, Megatron was transported to Cybertron himself, but Shockwave soon returned him so that further transport runs could be conducted.