In “Shooting into a Fight” (L’avant garde #39), Phenster addresses an age-old dilemma in D&D combat. I cover how the problem is handled in early editions and give my own solution in “Firing into Melee.”

On first reading, Phenster’s description of the “Friendly Fire Number” may seem complex. I attempt here to break down Hazard’s calculation into discreet steps. After some practice, I find it isn’t so difficult to do the quick mental math.

The task is less daunting if we remember the following points:

1. Throughout the text, Phenster uses only even numbers up to the maximum of 8. So we only have four options: 2, 4, 6, or 8.
2. We don’t have to take into account all figures in the melee. We only consider one or two friendly characters, between the shooter and the target, and only one creature as the target.
3. Like Hazard says, “You don't have to get it exactly right.”

Missile Fire into Melee [E]

“Remember that spells and missiles fired into a melee should be considered to strike members of one’s own party as well as enemy” (Holmes, 20).

Holmes gives no further guidance on the matter. The following method may be used to calculate the chance of friendly fire.

Method

1. Determine the friendly fire number (below).
2. Subtract the friendly fire number from the attack roll and add bonuses and penalties as normal to determine a hit or miss on the target.
3. If the natural dice result is the friendly fire number or less, a friendly is hit.

Short Range: According to Phenster, missile fire into melee is only permitted from the weapon’s short range. (But see below, Hail Mary [E].)

Target Has Precedence: In the case where the natural result would hit a friendly, but adding modifiers hits the target, then the target is hit.

Which Friendly is Hit: Phenster doesn’t say how to determine which of two friendly characters are hit. You could dice for it based on the relative sizes of the two characters, but that takes an extra dice roll. When two friendlies are in jeopardy, I call one odd, the other even, at the same time I call the friendly fire number. The attack roll then determines which is hit.

Sizes

Using Phenster’s examples, I extrapolate creature heights and add a couple other usual types.

To Determine the “Friendly Fire Number”

I break down the scenarios into three cases by the shooter’s position in relation to the target and allies. The shooter is attacking either from behind allies in melee with the target, from the target’s flank, or attacking from the target’s rear while all friendlies are opposite.

From Behind Allies

In the standard case, where the missile fire attacker is trying to shoot into a melee from the same side as the friendly characters, consider one or two friendlies in melee with the target. We start with the base number, then add and subtract for friendlies and the target by size.

Base Number:

• No matter who’s in the fight, the base number is 4.

Friendlies:

• Subtract 2 for small friendly.
• Add 2 for large friendly.
• Add 2, 4, or 6 for second small, man-sized, or larger friendly.

Target:

• Subtract 2 or 4 for larger target.
• Add 2 for small target.

Other Considerations:

• Assumes the friendly character is directly between the enemy and the would-be shooter. If the shooter is off to one side, but not flanking, subtract 2.
• When two friendlies are before the target, the shooter may move to one side, space allowing, so only one friendly is in consequence.
• The DM may add 2 or 4 for friendlies not in melee but masking fire in the middle field.
• In no case should the friendly fire number be lower than 2.

From Flank

In the case where the attacker is flanking the melee without a friendly in the way, we consider all friendly figures on any side of the target as a group. The number is predetermined, no additions or subtractions.

• Friendlies on one side: 2
• Friendlies on two sides: 4
• Friendlies on three sides: 6

Another way to think about this case, is simply 2 per side.

All Friendlies Opposite

When all friendlies are beyond the target, we calculate the number for one or two friendlies in the line of fire (as in From Behind Allies above), then subtract 2.

Modifiers to Mitigate Friendly Fire or No?

Hazard doesn’t count any modifiers in the chance to hit a friendly character. Should a shooter’s high Dexterity help to avoid friendly fire? How about a magic bow? Should a high-level shooter have a better chance?

The answers to these questions may depend on how high a Dexterity bonus can be in your game and how much magic treasure comes into the campaign. Another consideration may be the calculation required. It’s easy math for sure, but that extra step in the players’ minds takes a little of the immediate impact out of the dice roll. I like for everyone to know immediately when the dice stops whether the aim was true or somebody needs to make an apology.

The following rules take modifiers and high levels into account. You can use either or both with Missile Fire into Melee [E].

Add Modifiers to Mitigate Friendly Fire [E]

Use the modified dice result to determine friendly fire.

Add Level “Steps” to Mitigate Friendly Fire [E]

Add 1 to the attack roll for each “step” above the first on the attack matrix, one step being three levels for fighters, four for clerics and thieves, and five for magic-users.

Caveat: Using both these rules, a 4th-level fighter or a 5th-level thief (second step, +1) with a +1 Dexterity bonus for a score of 13 or more and a +1 magic bow at short range (+1), has a +4 on the attack roll, which allows them, in the standard scenario, to shoot into a melee with impunity. Careful.

Hail Mary [E]

It’s risky, but in a game where anything is permitted, players may want fire into melee at medium or long range. In this case add 4 to the friendly fire number for each longer range: medium +4, long +8.

No Shooting Into Melee [H]

“Once the party is engaged in melee, arrows cannot be fired into the fight because of the probability of hitting friendly characters” (Holmes 20).

“…and then melee is joined, after which no missile fire is permitted because of the danger of hitting friendly forces” (21).

In two of three mentions, Holmes interdicts missile fire into melee. Unsatisfactory as this may be, the easiest way to handle the situation is to disallow it. I include this option to remove any ambiguity, should the DM provide a list of house rules to players.