Transformers: The Game

Choose the Decepticons and choose "The Hunt For Sam Witwicky" level. Go to the sports shop next to the mall. Then, go to the gas station and face the mall. There should be a jump. Transform and go off the jump into the building on the right. Note: Make the jump off the side of the ramp and use boost when you are close to the ramp. When Barricade hits the building, make sure that he lands upside down (do not transform when this happens). Wait a few seconds and Barricade will flip over. When he does he should be bouncing up and down with his wheels on the ground, sitting still. This may require a few attempts.

Enter at the menu that has campaign and bonus features listed:

G1 Megatron
Down, Left, Left, Down, Right, Right, Up.

G1 Optimus Prime
Up, Up, Down, Down, Right, Right, Right.

Infinite Ammo
Up, Down, Left, Right, Up, Up, Down.

Jazz G1 skin
Left, Up, Down, Down, Left, Up, Right.

No vehicle's running on the street and no tank's/cop's attack
Right, Left, Right, Left, Right, Left, Right

Robovision Optimus Prime skin
Down, Down, Up, Up, Right, Right, Right

Starscream G1 skin
Right, Down, Left, Left, Down, Up, Up

Unlock All Mission
Down, Up, Left, Right, Right, Right, Up, Down

Unlocks Bonus Cybertron Autobot And Cybertron Decepticon Missions
Right, Up, Up, Down, Right, Left, Left.

Megatron is the final opponent in the Autobots storyline. He will first be in his jet form and shoot two rounds at you. Use your shield to avoid them. After firing two rounds, he will land. His next attack is ramming. You cannot hit him while he is still focused on ramming. When he stops ramming and stands up in one place looking around, pick up any car and quickly throw it at him. If not done fast enough, he will return to ramming. If that happens, wait for him to stop again. If done successfully, he will now attack you. Hit him in close range combat with your melee attacks. After a few hits, he will return to being a jet. After two rounds of firing, he will again return to the ground. In his second attack, he will use his ball and chain. Throw another car at him. If done successfully, he will attack you again. Use melee attacks on him. He will then become a jet and fire at you again after a few hits. Do the same as before to avoid the attack. After firing at you, he will go back to the ground. His third attack is the flamethrower. Be careful because it will be difficult to get cars to throw at him. When he is hit by a car you threw, he will attack again. Use melee attacks on him. For the last time, he will become a jet again. Use the same strategy used earlier to avoid the attack. He will land after a few hits and attack you with all the attacks he used previously. Throw cars at him after each attack. After that, you will fight him for the final time. Use melee to defeat him.

When you are fighting the cement truck Decepticon as Ironhide, transform and run him over to knock him down. Then, pick him up and throw him.

First, when you are fighting a decepticon, it will attack you. Run somewhere far from the decepticon. Just press: Circle, circle, Up, Down, R1, L2, Square and Left.

That way, you can destroy the decepticon with one shot. Example: Throw a car, Throw a tank{ Not Advised}, Throw a tree or fight it with melee attacks and shooting it. Just one shot, the decepticon is dead. Especially Megatron and the other decepticon. But if you missed, try throwing a some other objects like Lamp Posts. And don't stay to close to the decepticon while entering the code. I died once when I stood to close typing in the code.... Hehe.....