The Steelhaven finally makes contact with the Ark...and Grimlock isn't happy to find out that there's another Autobot leader out there! The Dinobot challenges his rival to Trial by Combat, but Fortress Maximus, still not recovered form the injuries he recieved while trying to rescue Buster, stands no chance...unless Blaster can find it within himself to step forward in his place. At stake is more than just the title of Autobot Commander - the very existence of Optimus Prime hangs in the balance!