There are a few ways to do this. Assuming you have beaten the story mode, you can go to the combat challenges and do the "Rumble in the Jungle" challenge. In the 4th round, clear all but the large charging guy. Place explosive gel and attempt to make him rush you. When he does so, make it explode and do as much damage as you can. Or, just allow him to charge into the walls. Another is just before
, in which you have 2 to fight. Just do not use gadgets and make them run into each other or the walls. Here are a few videos to video to help:
Campaign near the end:Rumble in the Junble path:Hope these help! If you have any suggestions lemme know!