Ben 10: Alien Force Hints

Play has 2 player mode and make sure one of you is the ice guy(idk his name)
then one of you must kill a bad guy and when he is falling Quickly freeze him and he will be frozen in mid air

another way is too knock the enemy back then freeze them sometimes they are almost laying on the floor
when they are frozen and dead when the ice breaks they will just fall to the floor

When u are swamp fire go underground on the pier level where the fuleing tanks are and every once in awhile when u come back up only the upper half of your body will be there while your legs will be under the floor

*NOTE this only works sometimes not all of the time