Firing into a Grapple?

[Caliber]

Improved Precise Shot [General]
Prerequisites
Dex 19, Point Blank Shot, Precise Shot, base attack bonus +11.

Benefit
Your ranged attacks ignore the AC bonus granted to targets by anything less than total cover, and the miss chance granted to targets by anything less than total concealment. Total cover and total concealment provide their normal benefits against your ranged attacks.

In addition, when you shoot or throw ranged weapons at a grappling opponent, you automatically strike at the opponent you have chosen.

Normal
See the normal rules on the effects of cover and concealment. Without this feat, a character who shoots or throws a ranged weapon at a target involved in a grapple must roll randomly to see which grappling combatant the attack strikes.

Special
A fighter may select Improved Precise Shot as one of his fighter bonus feats.

An 11th-level ranger who has chosen the archery combat style is treated as having Improved Precise Shot, even if he does not have the prerequisites for it, but only when he is wearing light or no armor.

The important parts are bolded up above ... I can't seem to find where the rules for firing into a grapple are. Anyone mind helping me out?

 

[Patryn of Elvenshae]

Sure! They're actually a footnote to a table of AC modifiers. The footnote reads:

3 Roll randomly to see which grappling combatant you strike. That defender loses any Dexterity bonus to AC.

It doesn't actually explain what random system to use, however.

 

[Len]

It's in a footnote in the Combat Modifiers section.
http://www.systemreferencedocuments.org/35/sovelior_sage/combatModifiers.html

 

[AuraSeer]

In the SRD, it's in the "Combat Modifiers" section, in the table of Armor Class modifiers. Look at footnote 3.

 

[Len]

It doesn't actually explain what random system to use, however.

My DM makes it a 50% chance if the grapplers are the same size, and weights the chance arbitrarily if they're different sizes.

 

[Patryn of Elvenshae]

My DM makes it a 50% chance if the grapplers are the same size, and weights the chance arbitrarily if they're different sizes.

Yeah, I've seen about a dozen different systems mentioned, and they all work more or less.

 

[Caliber]

And with a response time of 5 minutes we have a winner with Patryn of Elvenshae!!!

Seriously though, thanks everyone. I think 50/50 for same sizes and weighed against larger creatures will work out nicely.

 

[Patryn of Elvenshae]

And with a response time of 5 minutes we have a winner with Patryn of Elvenshae!!!

Woo! What do I win?

Seriously though, thanks everyone. I think 50/50 for same sizes and weighed against larger creatures will work out nicely.

Another system I've seen used is:

1. The smallest creature size in the grapple is scored as 1.
2. For each size category larger than the smallest size, multiply the score by 2.
3. Your chance to hit a creature is equal to its score / the total of all scores.

Examples:

1. Three humans are grappling, and you wish to target one of them. The smallest size is Medium, so Medium creatures are worth 1 point. There are three Medium creatures in the grapple, so your chance to hit your target is 33%.

2. Three humans are grappling with an ogre, and you wish to target the ogre. The smallest size is Medium, so Medium creatures are worth 1 point. The Large creature (ogre) is worth two points. There are 5 total points worth of creatures in the grapple, so your chance to hit the ogre is 40%, and the chance to hit any given human is 20%.

3. Three humans, a halfling, and an ogre are grappling with a Gargantuan dragon, and you wish to target the halfling. The smallest size is Small, so the halfling is worth 1 point. The three humans (M) are worth 2 points apiece. The ogre (L) is worth 4 points. The dragon (G) is worth 16 points. Therefore, there are 27 total points worth of creatures. Your chance to hit your target (the halfling) is 4%.

A variation on this also doubles the score of the creature you're targeting. This would result in the following changes to the above chance to be "on target":

1. 33% => 50%
2. 40% => 57%
3. 4% => 7%

This method may be more realistic and so might appeal to some players, but it also involves a bit more math. It's relatively easy math to do in a spreadsheet, however.