How do you beat megatron on transformers the game for PS2

Wait till he stops charging at you, then throw something at him. After that, he'll run at you. Simply punch him till he flies away again. He'll come back, swinging a ball n' chain wildly. Throw something else at him, then punch some more. He'll fly away again, then return and shoot fire. Throw, punch, etc. After this, he'll fly one more time, then return and charge again. He'll switch back to ball n' chain, then fire until he's defeated. Congratulations, you just beat the game.