Optimus Prime
The Autobots' leader is the biggest, strongest, and smartest. Optimus Prime makes the plans and protects the humans in the war with the Decepticons. He's awesome in big-rig mode and even more amazing as his true red-and-blue-armored self. You wouldn't call Optimus Prime cuddly, but he does care. He's just seen a lot of battle ... and he knows there's more to come.
Soundwave
A stealth drone and the Decepticons' spy master, Soundwave has no face and doesn't say much. He just quietly finds information to use against the Autobots. He can tap into any transmission anywhere, except at the Autobots' secret base. Soundwave's far-reaching tentacles can snap through concrete, but his main tools are the tiny Deployers in his chest. 
Bulkhead
This giant ATV is the muscle of the Autobots. But Bulkhead's actually kind of sensitive -- as Miko learns when she bonds with him. At first he was a little afraid of hurting his tiny partner, but Miko helped him get over that. Now she even pushes him to do things that sometimes get him into trouble. But when Miko's in danger, Bulkhead's there to protect her.
Starscream
This military fighter jet is Megatron's right-hand man. Starscream would rather sneak up on his victims than face them head-on, which makes him extra-dangerous. He's an expert planner, and that's one reason Megatron keeps him around. Starscream always shows respect to his general, but he's really just waiting for a chance to take command of the Decepticons himself. 
Arcee
Bumblebee
Ratchet
