The hardest game on Cool Math Games is called "World's Hardest Game." It consists of moving a red square to collect yellow circles while avoiding fast-moving blue circles. The game features 30 levels, and players can select which level to play.
A player's score reflects how many times someone dies in the game, and fewer deaths achieve a higher score. A level ends when the red square reaches the green beacon. Some levels have intermediate beacons as check points.
The first level contains one red square and four blue circles that move horizontally back and forth. Players must use vertical movements to move the red square in between the blue circles, eventually reaching the green beacon on the other side of the playing field.