I don't think it's possible to escape from HP. Everything you do or come up with will boil down to "abstraction for proximity to death".
The Madou Monogatari games didn't show any numbers at all; 'healthyness' was shown by facial expressions, from happy (full health) to less happy, somewhat troubled, distressed and knocked out. But that's really just an invisible HP value where a picture changes depending on what range it is in.
The NICE thing about HP is, for me (us?), being very familiar with the concept/system due to familiarity with DnD, DnD-based games or just games-that-adopted-HP-in-general is that it's understood on a basic level. Low HP bad, no HP dead.
Firstly, attacker and defender skills of different kinds (strike, dodge, strength, toughness, etc.) play into multiple rolls, any of which can influence the severity of injury. The attacker first rolls and determines how good the strike is, on a qualitative scale including e.g. "Excellent," "Terrible," and "Mediocre." The defender makes a similar roll to dodge, which if not successful outright may turn the blow somewhat less effective. Assuming the blow still makes contact, there's a roll against armor based on strength and weapon power. Whatever number on that qualitative scale makes it through is converted onto a scale for wound levels and applied to the character.
So first you roll the damage+accuracy, or just the damage? Followed by a dodge roll that reduces damage if it fails but doesn't fail too badly? And then you roll the damage that got through all that against non-static damage reduction, right?
Sounds like standard DnD to me, except they'd just roll the hit chance against a dodge chance, followed by rolling the damage if it hits and then subtracting according to damage reduction if the one being hit has any. They usually don't. Damage reduction is pretty rare, because the damage sources are usually not big enough to merit it being a standard occurence.
Sure, skeletons would have 5 resist to piercing/slashing (backed up by lore), but that's a monster. I'd LOVE to have 5 resist to piercing, then I could just wade into 5 million goblin archers and watch as their arrows have to roll to hit, then roll 1d6 against my 5 damage reduction...
I've played around with the idea of taking standard DnD (3.5e and up) armors and just reversing everything. The lightest leather armor usually gives 1 armor class and the heaviest platemail gives 8 armor class, AC being the abstraction for 'being harder to smack dead'. Of course the low AC armors have a high allowance for the player's dexterity-based AC bonus (being easy to move around in) while the high AC armors don't have this (even having a penalty to the player's dex-based AC bonus due to being cumbersome). This gives you a situation where a warrior with two left hands (clumsy, no dex) in plate mail and with a tower shield has more AC than a nimble thief in leather armor; he'll get hit less often, but if either of them get hit, they take THE SAME AMOUNT OF DAMAGE. What the hell?
So I usually think about making light armors giving high AC and player DEX bonus allowance while having the heavy armors give low AC, player DEX bonus penalties and damage resistance. Therefore a warrior in plate will be more likely to get hit than a rogue in leather, but he'll take a lot less damage. (Though I'd have 3 damage against 5 damage reduction come out as 1 damage taken instead of 0 damage taken, bowing to the death-by-1000-cuts idea)
Individual wounds are kept track of in buckets by severity. In order for lesser wounds to be meaningful, it must be possible to "die the death of a thousand cuts;" the cumulative effect should eventually prove overwhelming. My first idea here is to simply promote injuries when a bucket gets too full. You get a too many "minor" cuts, maybe you convert the next one into a "not so minor" cut. Another way to go, which I'm also considering, is to penalize toughness rolls based on degree of injury (measured by high water mark, I guess -- when you're bleeding out your guts, nobody cares how many papercuts you have).
So you're tracking a bucket per limb, stacking wounds untill they promote, and then repeating that untill the player collapses? But what's the effect of each wound, in damage? How does 5 nicks compare to 1 gash? Aren't you just abstracting HPs (which are already an abstraction) at this point?
I don't think healing should be done away with altogether, just made less effective and readily accessible. Wounds heal naturally over time, especially minor ones. There's no reason the system can't track all that. First aid should matter, and I'm not against some healing magic that's not dramatically more potent than first aid. Some injuries would be too severe and require the player to retire to town for the attention of, say, a surgeon. I see no reason for any injury to be ultimately incurable, though -- that would be anti-fun.
So a giant HP pool with innate regeneration, where a percentage of the giant pool gets "blocked off" if the wound is too serious untill the wound is fixed.
(Also, having to go back to town because bucket X got filled too far instead of bucket Y getting a promotion or two is
anti-fun in the extreme.)
What I'm getting at is that you're using HPs, you're just calling them something else and pretending you're not using them. There's no getting away from HP untill you find a simpler abstraction for health; anything that's more complicated is just HP with some smoke and mirrors.
I do very much like the idea of blocking off parts of the HP pool though. It's pretty common in some fighting games. Here your character takes damage to his hp bar in 2 ways...
First you lose HP due to getting smacked, let's say you lose 10% HP. That 10% HP lost is lost temporarily and starts regenerating immediately. You've got 90% HP remaining, but your
maximum potential HP is still 100%. If you avoid taking damage or tag out, it can regenerate back to 100%. Further hits you take are subtracted from BOTH your regular HP and your maximum potential HP (some types of attacks taking more from one or the other) leading to situations where a character could have 20% current HP remaining with 70% maximum potential HP. He COULD regenerate all the way back up to 70%.
Compare that to a character with 40% current HP and 50% maximum potential HP. There's less pressure here to play safe/defensive since he's close to his maximum current HP.
It's a really nice system for health. Of course, there's not that much room to enjoy the nuances of it in the breakneck pace of fighting games
So how do heroes do it? With amazing skill, naturally! Picture a barbarian wading into a roomful of rabble, tearing them apart by the dozens. In an HP system, if you balance an encounter like this to be challenging, the barbarian will be near death by the end -- his toughness is represented by the width of that bar. But how does he do it in your mind? He throws tables, he smashes enemies' heads together, he ducks a blade by a hair's breadth and then breaks the wielder's wrist for his trouble. He wears armor that deflects blows and keeps damage away from his vital areas. He doesn't suffer just few enough injuries not to kill him and then magically recover; he does apply his skill and resources to his survival at every moment. To me, that's a lot more interesting than playing a "tank."
That's the magic of flavor text. You can have mundane dice rolls with mundane results to your mundane HP pool, but if the message log says you cartwheeled into an axe kick which discombobulated the were-elephant, it's still awesome.
I think it would end up in a system where fights are about dodging or deflecting injuries rather than absorbing damage.
Exactly what I'm after. It does present a user feedback problem to be solved; I'm thinking about perhaps using floating text or something to show wound magnitude right by the action. I also like the tactical combat stuff from Laik's 7DRL's; perhaps there's a way to make all this dodging and such more of a concrete tactical subject.
I like Jeff Lait's 7DRLs too, even if they're tough love. If you want to make combat more interesting than
You hit. It hits. You hit. It hits. You hit hard. Victory, quaff potion, move on.
then it would certainly be awesome if you could take a look at [skills/attacks/movements/defensive abilities] that use a (non-)regenerating resource or cooldowns (or both!).
Take a look at DDRogue or PrincessRL too, the input-based combat moves are a
great way to spice up combat!