Incidental Damage While in Combat

[Donnadogsoth]

You can really hurt yourself in a fight. Imaging you're fighting someone in an alleyway behind a restaurant. Someone's dumped a range back there and there's a low brick wall and some shattered bottles and s*** lying around, and here you are wrestling (unless you're a kung fu fighter you're going to end up wrestling) and bash your lower back on the low wall and stab yourself on the glass and cut your head on the range lid and who knows what else. So, has anyone come up with any rules to simulate this sort of thing? Is this why people wear armour? Is this what hit points are really for? Maybe I need hit points.

[Slipperychicken]

What system? Environmental damage is pretty widely applicable.

In shadowrun 5e, I'd probably consider glass on the ground to be a very low DV damage source when rolling on the ground; it might cut up a guy in a t-shirt and jeans, but someone wearing armor is unlikely to be harmed in a meaningful way. Maybe make the guy soak 2P, AP 0 if he's using unprotected arms and legs to wrestle in broken glass.

In 5th edition dnd, I'd probably treat it like caltrops for damage when rolling in it (dex DC 15 or take 1 damage), but not for impeding movement. Someone in armor would not be harmed by broken glass on the ground.

[Talakeal]

This is the sort of thing I like to leave up to fumbles.

Of course every time you bring up the F word people start imagining guys cutting their own head off with a spear so ymmv.

[JeenLeen]

I haven't heard of anything specifically for that, but stuff like the Shadowrun example or D&D caltrops seems effective.

You should also take into consideration the health meter for the game. In D&D, you have a lot of hit points (at least at mid-level). While in most d10 games, you might have 10 health if you have stuff to magically boost your HP. Thus, something doing small, incidental damage in, say, Exalted 2nd edition is a bigger deal than D&D.
On the other hand, you could emulate it in a d10 game by something like a dice penalty due to hostile ground or some such phrasing. Maybe lower defense value by 1, not because your defenses are actually less, but to give more chance of some sort of damage to incorporate the chance of landing of a rusty knife along with the chance of your foe stabbing you with their knife. (not a great solution, I admit.)

That said, I think Exalted 2nd edition has some rules for environmental damage. Like being in a burning hot place can make you roll damage. Such could be used for stuff like hostile ground, though it'd likely be overkill for the example you gave.

For wrestling matches and such, I could see saying that some of the damage a PC/NPC deals is incorporating using the environment. The end result of the attack roll hitting was 10 damage, but that 10 damage is a mix of the fist's force and the fact that the dude landed on some glass.

[Anymage]

I have to agree with everybody else asking "what system"? Largely because in many systems, you are a lot closer to a kung fu master than you are to an average Joe.

Environmental damage can come either from an environmental hazard (think less "there's a range you can bump your head against" and more "fighting over an active volcano"), stunting by an enemy, or a flavorful way to explain a fumble. But be aware of the relative theme of whatever game you're talking about.

[Grod_The_Giant]

I have to agree with everybody else asking "what system"? Largely because in many systems, you are a lot closer to a kung fu master than you are to an average Joe.

Environmental damage can come either from an environmental hazard (think less "there's a range you can bump your head against" and more "fighting over an active volcano"), stunting by an enemy, or a flavorful way to explain a fumble. But be aware of the relative theme of whatever game you're talking about.

This. "I punched a guy and cut my knuckles on his teeth" makes sense if you're in a gritty, grounded game about regular joes thrown in over their heads. Less so if you're in a tense spy game about world-class special forces operatives, and absolutely none if you're talking about larger-than-life heroes.

The closest I can think of is something like Fate, where if your roll ties the DC you succeed with a minor cost ("you manage to pry the grate open, but you skin your knuckles in the process") or do no damage to your foe but gain a temporary advantage ("you don't manage to land a square hit on the guy, but he bangs his back on the wall; he's got a temporary "Aching Back" aspect now").

[Donnadogsoth]

Thanks for the replies thus far.

Also, implied but should be made explicit: What about being in a mass battle or riot and being unintentionally bopped on the head by a two by four or the like? Or getting sucked under and trampled by friend and foe alike? Are there any systems that simulate the sheer chaos of such a situation instead of cleanly separating the battle into PC-Enemy dyads?

[Anymage]

Being caught up in a surging crowd is best modeled by calling the crowd a environmental effect. Although remember again that PCs are protagonists. They may get trampled if they try to stand against (or swim against) a stampeding mob. But they only get accidentally bonked by their neighbor's sign if there's some narrative reason for it, and never suffer more than cosmetic damage in a wal-mart brawl over the season's hottest new toy.

[Slipperychicken]

Thanks for the replies thus far.

Also, implied but should be made explicit: What about being in a mass battle or riot and being unintentionally bopped on the head by a two by four or the like? Or getting sucked under and trampled by friend and foe alike? Are there any systems that simulate the sheer chaos of such a situation instead of cleanly separating the battle into PC-Enemy dyads?

I'd call it environmental. Make an appropriate roll to determine whether the character is struck by wayward arms (perhaps an attack roll or dodging one), and apply a small amount of harm, as dictated by the game you're playing.

For trampling, you'd want a roll to decide whether the character succumbs to the press of bodies, and then if he falls down (for that reason or any other) apply harm or damage as appropriate.

And naturally, I'd only do something like this for a true mass combat or other situation with large numbers of bodies that I don't want to model individually.