When you are Bruce Banner at the first part when you get teleported to the leaders place you will have to fight 2 big blue guys that shoot thier green thingamagigers. Go to the door at the end and make them shoot the door then go through the door and then you transform in the hulk but you fight half-life and and someone else (i forget his name) but also you beat the blue guys when they come through the door.
P.S. thrownig people of ledges is fun. try it on military guys when you pursue Ravage.