This is my first attempt at coming up with a real challenge, so any suggestions are appreciated and I'm open to adding/removing/changing anything to do with rules / the level etc...
I call it Tilt.
First, to set the stage: http://FantasticContraption.com/?levelId=12358
You will see the red block balancing on top of the pole. The goal is to knock the red block such that it falls on the opponents side of the pole. Now, take a second and re-read that last sentence. It's possible (and not difficult) to hit the pole such that although the pole falls towards your opponent's side, the block falls on your side of the pole (even if its not on your side of the stage). This would result in a loss for you...
You must build your contraption entirely behind the start of the incline on your side. No part of your contraption may be to the right of that mark (*EDIT when built... of course they can go up the incline when started), even if they are not touching the ground.
No real constraint on the # of pieces, so I guess lets just say under 55. Multiple contraptions are allowed. Catapults, no problem. Whatever you want to build and use. As in the majority of the competitions like this, the reigning winner stays until it is defeated and replaced.
I drew inspiration from soccer, wrestling/sumo, and several other places. I'm pretty new around here so if something like this has been done before I'm sorry! Good luck everyone!
The first challenger, a rather simple one to get things rolling - http://FantasticContraption.com/?designId=1048515
Edit: To clarify, you may not build any objects passed the start of the slope. Is that clear? If not, I can alter the level and clear things up.