The body count in D&D really bums me out, especially when it comes to my players (my kids).
The kill count of an adventurer who makes it to level 20 is only one seen by a small number of machine gun operators in modern times. Soldiers who kill in war have high incidence of PTSD and other mental illness. I have a hard time getting away from that idea that this Robocop II level bodycount really makes the game bleak and sad.
What if
- most enemies stopped attacking after half damage, and tried to reach safety instead
In my experience, fleeing enemies are usually dead enemies. It still happens from time to time, but not if they know and understand the PCs’ reputation.
- when you take half your hit points worth of damage you get a level of exhaustion
- when you come back from zero hit points you have a level of exhaustion
If these are meant to disincentivize fighting it might work, but I recommend incentives, instead. Or at least additionally.
First of all, most enemies must be willing to work things out non- (or less-) violently with the PCs. And this needs to be telegraphed to the players. If they don’t know it’s the case, it might as well not be.
Second, the enemies have to offer the PCs (or players) something of value through their existence.
This need not be tangible. For instance, if the PCs initially fight them, they could visibly gain respect for the PCs during fight and may even become friendly by the end. Future interactions would likely not involve any fighting at all, except for fun.
- most opponents swoon or cower after 3/4 damage
Much easier to just make damage non-lethal. Saturday morning cartoon conventions.
- if you have killed a person, on a long rest you had to make a flat d20 roll and beat 10+ the number of people you killed or your rest doesn't clear any exhaustion
I don’t see why you should only be bothered by the kills of the day. Or is that meant to be cumulative over a lifetime? In which case, the campaign will probably end pretty quickly. Exhaustion gets pretty bad as it stacks up.
Also, what counts as a person?
question: does that just ruin D&D or could it still be fun?
My experience is that punitive measures usually do bend the game toward unfun, but that doesn’t necessarily have to be the case, perhaps.
If I were trying to steer players away from (lethal) violence, I’d prefer to look for carrots to offer (as indicated above), but I might also keep a stick in my back pocket.
For me, that stick would probably be in the form of an uncontrollable growing bad reputation that is rooted in the truth of the PCs’ actions (but need not adhere to truth, of course).