
Here is an enemy event. The enemy's health is configured and controlled by a variable. There is also a variable for the players health. When this variable hits 0, the game over screen appears. The trigger is set to "Event Touch" and the movement is set to "Approach".

Here is a part of the "Health HUD" common event. As you can see in the top, if the variable exceeds the maximum amount of health, it sets it back to 6.
This is set up through pictures, as you can see. There is a switch to toggle the HUD display on and off, for e.g cutscenes.
This system was very easy to set up, and it only took a matter of minutes for me to make it. It is still not perfect, and I'm looking for some ways to improve it. Post your suggestions down below! :)