Sure! Here's a simple example of a parkour fighting game implemented as a single HTML file. Please note that this is a very basic implementation and can be expanded upon to add more features, levels, and complexity.
To play the game, you would need to open the HTML file in a web browser, and you can control the player by pressing the up arrow key or the spacebar to make the player jump. The objective is to avoid colliding with the blue obstacle by timing your jumps correctly. If the player collides with the obstacle, a game over alert will be displayed, and the game will reset.