You'll need to call the renderStats() function whenever you want to update the stats displayed in the stats box at the bottom of the game screen. The template has a line under "Player" section that calls the renderStats(); function when a coin is moved on by the player character. To update the hitpoint stat during combat you'll need to add renderStats(); somewhere in your "Combat" section, like after an attack. You can also add it near the end of the "Player" section when the player moves to update every time the player takes a step.