I’m much more inclined to go with the unplayable idea. Characters based more off of mental or spiritual abilities should be as viable an option for harming other characters as those based off of physical abilities. It brings more balance if you can die from negative mind or soul.
Why should physical characters be the ones with the least disadvantages and the hardest to kill? That’s something that’s always boggled me about other games. Even if you don’t want to call it death, the idea that characters need to look out for more than physical abilities if they want to remain playable is a good one. It’s only fair. Yes, if you knock someone out, you can do physical harm to them more easily. But why should you have to rely upon that? Why should the body stat govern so much in terms of life and death? That’s the part that lacks balance, and the idea of mind or soul leading to death or some sort of equivalent balances things out further, and makes characters who aren’t combat-savvy in terms of their athleticism or martial abilities a much more feasible option.