Here's an aspect of D&D which has been bugging me more than a bit lately: shooting into mêlée.
Basic D&D doesn't address it, beyond a throwaway line in the '78 Basic Set that flatly forbids shooting missiles into a mêlée involving one's allies. From the '81 Basic rules onward, it's never mentioned: not explicitly allowed, not penalized in any way, and not verboten either.
Then there's AD&D, where any shot into a mêlée means the DM picking a target at random before the attacker rolls to hit. I like that this is chaotic and damnably realistic (no degree of archery skill could ever truly prevent friendly fire); I don't like that it means errant arrows from very high-level allies are more likely to strike a friend than wayward missiles shot by nameless henchmen.
Finally there's the d20 system, where you take a −4 penalty when shooting into a mêlée. As simple and elegant as it is boring and bland.
I'm tempted to say that the d20 rule is the best of the lot, only it still doesn't sit well with me. Shooting into a mêlée with friendlies just plain should involve a non-negligible chance of hitting an ally. A mêlée is just what it sounds like: a mixed-up, constantly dynamic, chaotic scrap of all combatants dancing and dueling and wrestling and grappling—not the static picture of everybody's miniature sitting in its designated square on the tabletop! So I'm thinking—even though it really does complicate things—I actually need to combine these rules into something that works for me.
And I really do hate increasing the complexity of Basic D&D's combat like this, because it goes against the very spirit of the Basic/Expert game to do so. But I can't just stand back anymore and let my games carry on where a few fighters tank for the party, and archers stand back and plink away and never face any danger. Most monsters encountered in a dungeon just don't have ranged attacks—it's a fact of the game—and not every encounter even with humanoid monsters is going to involved bow-and-arrow-armed humanoid monsters.
Frankly, it's making things far too safe and cozy for the ranged attackers. That's my real beef with Basic D&D (from '81 onward at any rate) remaining silent on the shooting-into-mêlée issue. It's license for anyone with a bow-and-arrow to hang back and let the sword-and-board armed fighters do all the dirty work. And certain players (you know the type) will even always make a point of defaulting to archery for precisely this reason: it keeps their character's skin out of the proverbial fire most of the time.
I hate that.
So something really must be done to discourage wanton and careless shooting into mêlée. But it makes no sense to have a rule where a high-level archer's +10 bonus (or whatever) to hit the desired target translates into a +10 bonus to hit a friendly if said friendly should twist into the arrow's path while his sword is locked at the crossguards with that of his foe. Presumably, said archer (being a heroical fantasy character of some stripe) is making like Legolas and holding his shot for the right moment to prevent exactly that sort of thing. A balance must be struck, in other words, between realism, fantasy, and a certain degree of rules simplicity (although this last one might just have to be sacrificed for the sake of any rule worth implementing).
So after pondering this and mulling it over and looking up how various editions and clones have handled it, I've settled on a prototype rule that I'm going to test-pilot at tomorrow's game. Here it is:
• All missile-fire, whether shooting or throwing, is either aimed or volleyed. The former means that you take careful aim at a specific target, but that takes time and concentration; ergo (as with casting a spell) you can't move and aim in the same round. A volley is a normal missile attack as per the regular rules of Basic D&D: you can move your encounter speed and still attack; but, when you fire into a group (any group, whether a band of enemies or a mêlée involving enemies and allies), the target of the attack is determined randomly before the to-hit roll is made.
• Characters can generally only aim out to close range; any attack at medium or long range must be a volley. The one exception to this rule is the archer character class I'm using in my house-ruled campaign: 2nd level and greater archers may aim at specific targets out to medium or long range.
• When you volley into a group, the target is picked at random as per AD&D: counting each dwarf-sized or smaller character as 1, each man-sized character as 2, each ogre-sized creature as 4, and even larger characters as larger numbers, assign points on a die and roll. If you volley into a mêlée involving a halfling and a fighter on your side against two hobgoblins and an ogre, count off—halfling 1, fighter 2–3, hobgoblins 4–5 and 6–7, ogre 8–11… and roll a d12 to see who gets hit (rolling again on a 12). The attacker's full to-hit bonus and all Dex and magic adjustments apply to the attack roll.
• When you aim into a group of only enemies, that just means that you're giving up movement for the ability to pick your target; otherwise it's no big deal. But when you aim into a mêlée, you take a penalty on the to-hit roll that depends on the number of allies you have in the fight: −1 for each dwarf, gnome, or halfling; −2 for each man, elf, or orc on your side; bigger penalties (−4/−8/etc.) if you happen to have large animals or monsters on your side in the scrap. If you hit the target you were aiming for, great, you nail him and deal damage normally. But if you miss, some other random target in the mêlée may take the arrow—as above, assign everyone involved in the mêlée (including the archer's intended target, even though the first to-hit roll was a miss—the point here is that it's pure chaos and just never know) some points according to their relative sizes, and roll a die to see who catches the flak. But now, to account for the fact that the shooter was specifically trying not to hit friendlies, the DM makes a second attack roll on the chosen target as if the arrow had been fired by a 0th level human with average Dex and a non-magical bow—THAC0 20 (or to-hit bonus +1), in other words. Kind of like a fixed-position arrow or dart trap. If this attack strikes the target, voila, friendly fire; if it misses, the arrow flew wide and hit nothing.
This seems like a rather complex procedure, I'll admit. But it also comes together as pretty reasonable and straightforward, at least in my head. Hopefully, most players will simply take the hint and not shoot into mêlées with friendlies. But if they insist, I don't think it's too hard to take a look at the situation, ask them if they're picking targets carefully or just volleying into the group, applying the penalties and making random target rolls, and then occasionally making a follow-up attack at THAC0 20 on an aimed shot that missed.
I guess we'll find out whether I love it or hate it tomorrow afternoon (the beginning of Barrowmaze campaign: month nine!).
EDIT: Two small tweaks to the above house-rule before I implement it. First: to emphasize that aiming doesn't take as much concentration as spell-casting, and won't be disrupted by damaging the archer, I'll tone down the movement penalty to half encounter speed, similar to Turning Undead or a Fighting Withdrawal. Second: given that shooting through soft cover imposes, at worst, a −4 penalty to hit for full cover, it makes sense to reduce the penalty for aiming into mêlée to become −1 per man-sized ally or per two dwarf-sized allies, maximum −4.
EDIT THE SECOND (as of 8:52 PM): Just got home from the game shop. Just had a downright intense game session. The players all grokked the missile combat rules pretty much immediately, they understood the underlying logic and were able to apply the modifiers themselves without my really having to remind them. The effects of friendly fire and the chances/frequency of it happening felt realistic, or at least realistic enough to feel right for a game of D&D. So in spite of the extra fiddling and extra dice rolls, I'm keeping this one. It worked.