While the Autobots continue their battle at the Earth's core, Jack learns more about Optimus' history on Cybertron.
The Autobots team up with a surprising ally to save Earth.
The Autobots discover that Dark Energon is responsible for Earth's recent natural disasters.
When the Autobots learn of the Decepticons' plans to build a Space Bridge, Optimus decides to face Megatron once and for all.
Ratchet's devotion to the Autobots is tested when he believes that he has perfected the formula for synthetic Energon. But when Ratchet uses himself as the test subject, the synthetic Energon begins to alter his personality.
The Autobots and Decepticons race to claim a magnetic weapon. In the ensuing battle, the Bots are forced to fight while stuck together!
During a battle between Bulkhead and Breakdown, Breakdown is captured by Silas and his M.E.C.H. agents so they can dissect him to better understand Cybertronian biology. Figuring Megatron won't mount a rescue for a fellow Decepticon, Optimus Prime assembles his team to do so, much to Bulkhead's shock. Initially, he refuses to help his archenemy, but Miko convinces Bulkhead to go, so he can get a long awaited rematch against him. Bulkhead is first to find Breakdown and the two must work together to escape the savage M.E.C.H.moreless
Starscream begins plotting his revenge against the newly revived Megatron by stealing a Dark Energon crystal with which he plans to resurrect Skyquake. But when Miko and the others follow the Autobots to Starscream's coordinates, the two competing GroundBridges get distorted and accidentally send the kids to another dimension where they can't be seen or heard by the Autobots. Unfortunately, a zombie Skyquake is also stuck in the Shadowzone with Miko, Raf and Jack, putting their lives in danger.moreless