Play the game "Red Ball 4" on CoolMath-Games.com by using the arrow keys to move the main character, the titular red ball, back and forth through each level to reach the end. You can also use the up arrow key to jump, which is useful for overcoming obstacles.
At the start of the game, you are given the option to select which level you want to play, though on the initial time playing only the first level is available. During each level, you use the left arrow key to move the character to the left, the right arrow key to move the character to the right and the up arrow key to make the character jump. The majority of the gameplay involves using these keys to move the character across each level, though over time new obstacles are introduced.
The obstacles in each level vary, with some consisting of high platforms that require you to move a box underneath in order to reach. Many levels also include enemies that damage the character when touched. The character has a health meter that consists of three hearts, with each enemy dealing damage equivalent to a single heart. It is important to note that the character only incurs damage when touching the enemies from the side. If the character jumps on top of them, it defeats the enemy.