Transformers One

In a world of sentient robots on Cybertron, Orion Pax, a mining robot without a transformation cog, discovers a conspiracy involving the planet's leader, Sentinel Prime, who has been secretly aiding alien invaders. Orion and his friends uncover evidence of Sentinel's treachery and rally against him, leading to a climactic battle. After a series of conflicts and betrayals, Orion ultimately transforms into Optimus Prime, defeats Sentinel, and vows to protect Cybertron from further threats, while Sentinel's forces regroup under the name Decepticons.