Fan Casting Rebuild of Transformers

Cybertron, the home planet of the Transformers ravaged and death, consumed by war between the Autobots and the Decepticons lead by both Optimus and Megatron respectively. now in a Cold War esque state Optimus and a few other Autobots now have to find the Allspark in hopes to restore their planet engaging on a ship called the Ark along with the Decepticons who are on their way chasing them with the Nemesis they both crash land on a planet called Earth where they befriend some humans to be their allies and now with a vow to protect earth from the Decepticons so they don't want it to suffer like Cybertron (the first chapter in a rebooted universe)