I've always loved the idea of videogames where you are still fully functional at 1 HP
Like, imagine you're at work, and Cheryl from accounting comes over to you holding an invoice all like "Hey, can you handle this?"
But when you take it from her she gets a tiny paper cut and then falls over dead.
@NullNowhere @neatchee Traditionally, level-based HP system treat hit point damage as "the ability to minimize a wound" -- so 6 points of damage would be a fatal blow at 1st level, but at 5th level, you step back at the right moment and it's a slight scratch.
GURPS, OTOH, has even light injuries imposing a shock penalty for a round (making it better to focus on defense), with increasing penalties as you fall closer to death.
@LizardSF @NullNowhere I'd be interested in trying to create a system where HP is static across levels, with a performance penalty as it is reduced, and a different mechanic - a stagger gauge? - that controls whether or not the next attack will cause damage or not.
e.g. blunt attacks deal more stagger/knockdown, while slashing attacks deal more damage if they connect.
@neatchee @LizardSF @NullNowhere As a result, you now have multiple ways of dealing with damage which reflect different resilience mechanisms. And really what you accrue is danger – the danger of actually being injured in a notable way by the actions which have been taken against you. You don't know how badly until you get a minute to check yourself out.
I think you'll find that adds a certain level of mystery that is currently lacking in the process.
@lextenebris @LizardSF @NullNowhere This is good stuff! Of the systems I've seen (both in this thread and my experience playing ttrpg) I think this honestly most closely reflects what I would expect.
In an ideal world I would set a threshold for HP below which negative modifiers start to apply. Probably a simple reduced chance to hit targets. This would help discourage risk-taking as your health gets low.
In other words, your "danger" increases steadily as you take damage, making you less able to resist more damage, and when your health gets low enough it impacts your ability to successfully take actions.
Love this theorizing 
@neatchee @LizardSF @NullNowhere You want to make sure that the death spiral that so ensues is not so absolutely brutal and obvious that the moment you set foot on it, you know you have nowhere to go but down – so the rest of the interaction turns into how can you pause the degeneration long enough to get a few more moves in.
There's the point where balance is going to be the hardest. It's certainly possible to make it happen but that's the direction to look for work.
@lextenebris yeah that would definitely be something to iron out in play testing, but given the variables available for tweaking there's probably a sweet spot that works. You'd also want to carefully configure things for how this resilience value is removed; plenty of options here and a good lever to move when balancing.
Remove when healed? Consumables? Passive regen? Use an action to recover?
The ability to manage that value presents all sorts of interesting decision making opportunities, which IMO is the best and butter of fun combat
@neatchee In my own games, I generally find that there are really only three states that are meaningful (though one of the states is diverse).
You can be healthy and fully functional.
You can be physically or mentally impaired in some way.
You can be dead.
The last state is no fun at all so it almost never happens. Correction: It almost never happens without the player's explicit demand – which happens more often than you might think. Sometimes you just want a really good crescendo.
@neatchee For example, one form of impairment is being disarmed. Your sword is not across the room and isn't in your hand anymore. You've taken a blow to the head and can't focus enough for a telekinetic push. The oxygen has been drained from the room so no fire bolt. Your sanity just got seriously eroded and you can barely focus enough to stay upright.
All of these are fictional descriptors which limit your choices of action, effectively impairing you.
@neatchee And if you really need a death threshold, set an arbitrary number that is convenient to one of the dice that you're using and say that under certain circumstances death can catch up with you and you have to roll over the number of impairments you have or die.
It's not a lot of fun, but if you put the time of the check off a bit, characters have time to do things before the deadline. Players have time. And that's fun.
@neatchee @LizardSF @NullNowhere Savage Worlds does what you are thinking about. The main characters all have 3 wounds, while the extras (disposable minions) only have one. You also get a penalty to your rolls equal to the number of your wounds.
It does suffer a bit from the problems others have pointed out (it has a very punishing death spiral, because healing is not easy at all), so your best bet is always try to avoid wounds.
@nikelui @LizardSF @NullNowhere I sort of recall playing some d&d5e homebrew that borrowed that mechanic, but it felt overly simplistic on top of the death spiral.
I remember feeling like once you got a single wound my efficacy was so dramatically reduced, and my likelihood of being wounded even further increased as a result, that we all got unreasonably defense-oriented
Maybe that was just because it was shoehorned into 5e? It wasn't very satisfying either way
@neatchee @nikelui @LizardSF @NullNowhere The death spiral is possible, but mitigated by other game mechanics such as Soaking damage, and spending Bennies (similar to Luck Points in some ways) to reroll saves etc
In practice it hasn't affected our table in 6 campaigns and dozens of one shots.
@neatchee @LizardSF @NullNowhere Savage Worlds does exactly this by abstracting damage with it's Shaken and Wounds system.
Important Characters and Players (aka Wild Cards) have 3 Wounds. Background characters and minions (aka Extras) have 1 Wound. When a character is hit, if damage is equal to, or greater, than the target's Toughness+Armor, then they gain a status called Shaken. For every increment of 4 damage beyond that, they suffer a wound. Shaken is easy to remove, Wounds have to heal
@neatchee @LizardSF @NullNowhere Damage can be soaked to avoid taking Wounds. Shaken prevents a character from taking actions, but still allows them to move. It's super easy to remove, but if a character fail to do so, it makes it easier to Wound them.
It works really well at abstracting the complexities of combat and health, while still giving both sides the feeling of achieving something. It's the most elegant system for this I've seen, and avoids the "War of Attrition" from HP systems
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