well i thought it would nice to put up ideas on making traps on some of the maps.
one possible of doing is having small holes in the wall that when you get near it shoots out the trando knife mesh whcich has a kill zone around it.
now to the force push a simple invisible wall that when you push a specific button or trigger it comes up and pushes you back or up or whatever.
That would be cool!!
I have been playing with things like this as well, a arena idea that I had a while back just haven't finished yet was lava or water in the bottom, and then two bases that are floating. and there is a drop out flooring in it. that can be triggered from the top.
Another one I have worked on some is a small arena, that is close to releasing and it has several traps in it. and lots of moving pieces.