In addition to the Balloon Survival competition, the Wonderful Robot Carnival format lends itself to special challenges and head to head competitions. Bouts like the 'Die Shoot' use a simple, straightforward format, with very few rules or restrictions, yet involve a lot of thinking, strategy, speed, and performance.
The 'die' is a cube, 10 cm on each side, and weighs 30 grams. It's placed in the center of the playing field. Each robot is assigned a direction, and tries to push/kick/throw/move the die in that direction until it crosses the opposing goal.
Blocking is often a good strategy to keep your opponent from scoring.
Size can play an important role, but doesn't guarantee winning by itself.
Everyone participated in all of the competitions, even if the game rules or equipment may have put them at a disadvantage. Being there, taking part, and experiencing the whole event were the most important factors for most of the participants, no matter how much they wanted to win.
Here's one of my favorite Die Shoot bouts:
2nd Wonderful Robot Carnival Website (Japanese)