A good hardcore Pack Mod, Longer You Live in A Minecraft World You would lose health, Example: The Player Will Start out With 20 Health Or So And Like 10 Minecraft Days you lose like 1 Heart or so!
Good Idea Ayy!
Something similar, if not exact.
I have a config file option in my mod to change the players starting hearts. So if you set it to 3 or 5, you start with that many hearts.
There is an edible item to add a heart container.
Mod has tons of other stuff too but, its close https://minecraft.curseforge.com/projects/cyclic