Radar Rat Race takes the gameplay of Rally X and puts it into a rodent context. You control a rat, who must grab all the pieces of cheese in a maze, and flee from all the other rats. Once you reach a barrier in the maze, you are automatically rotated, but you can always manually change direction.
There are red ones who chase after you, and black ones who are activated when you get close to them - both types kill you on contact. When they are close, you can activate a Star Screen to block them off.
The Radar of the title is on the right of the screen, and shows you where each piece of cheese is, although the actual maze is not illuminated, so your next snack might be further away than you think.