This relatively quick mission will see you attempting to stop an Autobot transport carrying the planet's remaining reserves of Energon back from the ruins you excavated earlier and to the Autobots base, where the Ark sits in waiting. You will begin the mission in your vehicle form, a sort of buggy with a mounted gun and rockets. You will have to use these to destroy the treads of the massive transport as you drive underneath of it.
Before you can do that, though, you'll have to watch as Starscream's idiotic air assault plan comes to a head. He and a number of other flying Decepticons will assault the Autobot transport, which is conveniently equipped with anti-air guns. You will find yourself bouncing from plane to plane on your descent. Smash through the first group of cars ahead immediately, wasting the ones you miss with your rockets. Reload and snag up some ammo from the raised hill in the center of the area. Get ready, as more enemies in their vehicle forms will be coming up to assault you. Your first task will be to eliminate the armor protecting the treads in the back of the vehicle.
Head to the back of the area and focus your fire on the red areas of the treads. With them gone, blast the vulnerable wiring behind the armor to cause a malfunction in the wheels. With the back two wheels gone, refill your ammo and rocket ahead towards the front treads. You probably will have smashed up the back treads a little earlier than the game anticipated, so head past the front treads and to the waypoint marker ahead, where you will find a small base filled with Autobots. Destroy the Autobots in your vehicle form; you are less vulnerable in this form. With them gone, use your grappling hook to yank down the door ahead, and grapple over to the platform sitting in the acid ahead. Use your grappling hook to navigate safely from one platform to the next over the acid. You will soon reach a larger platform where a group of enemies lies in wait.
Eliminate the enemies, being sure to watch out for the grenades that they will be tossing your way, and wait on the platform for the giant transport to get close. Blast through the red armor and destroy the wiring in the treads to bring the transport to a stop. You will now be joined by a few Autobot heavy soldiers. They will start out at the far end of the battlefield, so use the distance advantage to pelt them with ammo from afar before going in close for the kill. Watch out for the smaller vehicle form Autobots who will try to distract you from your real prey. Blast these smaller enemies out of the way with your rockets before getting back to the fight at hand. When the large Autobot heavies shield themselves, use your missiles to take out the drones protecting them with ease. The homing capabilities of the rockets should make this a snap.
After this battle, a group of five more Autobot vehicles will rush in, accompanied by another heavy soldier. Use your vehicle form's flanking abilities to get behind the heavy and pepper it with fire from behind. With him gone, focus the rest of your attention on the light soldiers and you should have the area cleared out in no time flat. With this, you will have completed the mission and brought the transport to a halt. Unfortunately for you, the Autobots had a backup plan. Huge jets will pop out from the transport and blast it off into the sky. You will have to use your grappling hook to latch on at the last second as the transport flies off into the sky.