W’gild might be a viable platform for doing away with hitpoints, trying to do avoid the http://tvtropes.org/pmwiki/pmwiki.php/Main/CriticalExistenceFailure
A tall order, but some interesting mechanics could be extracted from the experiment even if it fails.
Without hitpoints, what does it mean to defeat an opponent?
That can vary a lot depending on what it is - utter destruction could be necessary in the case of undead, or severe enough incapacitation could do the trick for living humans.
Even then, what is necessary to kill an enemy?
Cutting wounds cause bleeding, so cutting them up for long enough will eventually cause an enemy to bleed out and die, so that’s an option. Would be decently close to a hitpoint system, except every cutting attack is extra “poison”.
Critical hits, like a good whack to the head with a mace, are good for reducing attributes (dexterity, reaction time, etc.), meaning you get an unstable equilibrium for the enemy once they take a couple of bad hits.
Breaking armor could be important here - one might have to create the vulnerable spots first with a heavy weapon, before finishing off with something else.
Some simulation of adrenaline could help in the mix - perhaps gotten over the course of the battle, or depending on how many normal blows were received? Would entail in some moderate resistance to pain/crippling blows/etc. Would it entail in faster bleeding out due to increased blood flow? I might be off base here.
If there’s a thing most likely to be salvaged if this doesn’t pan out - it’s the ideas that defeat doesn’t have to mean the same thing for every enemy, and there hopefully should be different tactics used when dealing with wildly different enemies.