You can change the health and damage per hit at the start. Use "A" and "D" to control red. Use the right and left arrow keys to control blue. Press "S" to stab for red. Press the down arrow key to stab for blue. Press space if the sword doesn't match up with the block. The game ends when you click "End".
For an extra challenge, play it by yourself (although that's probably what you're already doing)!
