"If a projectile is used, it must have a frontal area greater than 10 square inches"...
And you can't spray oil all over the opponent's robots, and you can operate the robot by having it react to the corn, the walls and the air, and after competition, your robot becomes property of FIRST. So much for off-season events

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Given the smaller size of the robots, I'd say that Maize Craze was more like non-destructive Battlebots than today's FIRST robotics. But good find though, since I've only seen a few pictures of Maize Craze and knew only that it involved a playing field of corn.