Thanks you so much for the reply SilverWarior!
The game is called Cossacks 3, have you heard of it?
The dev said to make the units health drain, you should write your code in nothing.inc, next to famine check (use it as example). He said the famine code should get me started so use this as an example because essentially draining units health is similar to the famine code when food runs out units start to die. I attached the whole nothing.inc file to hopefully decipher it.
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