Nikon Coolpix 990.

This shows what can go wrong even with rehearsed "air fights". I guess the kick should have gone over his head, but it didn´t. The kicking guy makes his kicking arch about one decimeter to the left of the head (from his viewpoint, in the image the kick was too far to the right) and the foot is on its way down when the crouching guy is already on his way up again. The kick didn´t seem to contact too badly, but still the guy was just about as groggy one can get without serious injury. Amazingly he did continue the show 20 minutes later.
Kids, don´t practice this at home...

Nikon Coolpix 990.

Images below are from the Sony TRV410:

This is about the same moment as the topmost image from the CP990, but from the other side.

Then he just falls together. This is no game.