You can fly! Flying is fun, swooping and soaring, going as fast as you want over, under, around and through things. You point in any direction and your anti-gravity rings fly you that way. But flying is also very dangerous! Touch anything, at almost any speed, and you're dead-- splat!
The time is the 26th Century. The place is a 'flyland,' an adjustable-gravity, half-kilometer-square surface high over an ocean, far from any land. This flyland, Ball Game, once a sports arena, is utterly flat and featureless, making it a good place to learn how to fly-- so it is your 'Trainer.' Not that it isn't dangerous...
A sci-fi flying person vs. robot battle game. This is the Flyland Wars Trainer. A robotic enemy seems to vastly outmatch your necessarily hand-thrown weapons. But you can fly! You can think! You are creative! Sometimes it hardly seems fair...