CapnZapp
Legend
The problem is that this is a massive increase in lethality - it is a bigger change that you'd think.The -10 hp helps somewhat. Even better would be a knocked out rule. Any character dropped in combat would be knocked out/ out of action for d6 hours regardless of applied healing short of a heal spell. So once a character goes down then they truly are no longer a threat and thus there would be no sane reason to keep attacking. No longer would healers just wait until someone drops to heal them. It would become vital that all party members stay above 0 hit points.
Not that that is necessarily a problem if you know what you're doing, but there are reasons why it isn't in the game:
- If you can't cast a spell to bring back a fallen ally to the combat, things become much more dangerous.
- The game has never been built around the idea that zero hp is a big thing.
- You become much more sensitive to bad luck.
- It is no fun sitting out some adventuring fun just because you're knocked out for hours.
And then we have thrown out the baby with the bathwater. In comparison, the -10 rule (you "bottom out" not at 0 hp but at -10) tweaks the game just enough for a first level spell to not automatically be enough to bring back the fallen ally, which is all you need.