A natural 1 on a d20 always misses. This is unchanged.
The chance of hitting something else is determined by the natural result of an otherwise missed roll. This is called the Wild Shot Range.
Condition | Wild Shot Range
-------------------+--------------------------------------------
Normal | 0 (no chance of a Wild Shot)
Ranged into Melee | +4
Melee into Grapple | +4 (target loses Dex bonus to AC)
Range into Grapple | +8 (target loses Dex bonus to AC)
Melee Obstacle | +2 (eg. the target pulls a chair in your way)
Cover | +4 (eg. A creature in front of your target)
Better Cover | +8 (eg. A creature is behind an arrow slit)
Under normal conditions, we don't care where the shot or blow falls on a miss. 50% of the time your ammo breaks or is otherwise lost.
For creatures to provide cover, they need to be the same size or larger than your target. A creature smaller than your target can be used as a Melee Obstacle.
Your target also gets "Better Cover" if there are 2 or more creatures in front of it. The target's AC is also +8. The Melee Obstacle also gives your target a +2 to his AC. A melee obstacle is some object that is between you and your target that doesn't grant him cover but does get in your way. For example, if the target pulls a chair between you.
A natural 1 is always a miss and not a Wild Shot. If your attack roll is a miss otherwise, a natural roll of 1 plus your Wild Shot Range is a Wild Shot.
For example, if your ranged attack is with a target that is in melee, your Wild Shot Range is:
+4 for Ranged into Melee.
If someone is standing in front of that same target, your Wild Shot Range is:
+4 for Ranged into Melee and
+4 for Cover for
+8 Total.
In the first example, if a natural 2-5 misses your target, you have a Wild Shot. In the second example, if a natural 2-9 misses your target, you have a Wild Shot.
You only ever have a Wild Shot if you would have missed your target's touch AC.
If your attack is Wild, determine where your shot/blow fell. If there is cover or obstacles involved, the blow will always fall on the closest one. Where there are more than one candidates, determine randomly giving weight to size.
Once object or creature is determined, roll an attack against the object or creature. Because you are not trying to hit the target, use only adjustments that are inherent in the weapon, such as masterwork, magic bonuses and the creature's strength. Do not use bonuses that are inherent in the creature attacking, such as your base attack adjustment, feats, and dexterity. The reason strength is included is that its bonus to your attack roll is due to your ability to plow through armor. Dexterity's bonus is due to making a well placed shot.
For medium sized inanimate objects, you need a 5 to hit (10 - 5 (0 Dex)). In most cases, you can take 10 against inanimate objects. Roll to hit against the target's normal AC (with Dex bonus if not otherwise denied.)
Most inanimate objects will break or be tossed aside on a hit.
An Example.
Grog is trying to aid Korg. Korg has just been attacked by a ghoul that is on the other side of him from Grog. Grog has Precise Shot and Point Blank Shot (+1). His base attack adjustment is +5, Dex +3, his longbow is +2 and +2 from Str. Korg's AC is 19.
The ghoul is 30' away. Grog' attack roll is +11 (+5+3+2+1). His Wild Shot Range is +8 (2-9) because the ghoul is in melee and Korg is in the way. The ghoul's AC is 18 (14 + 4 from Korg's cover).
While Grog' Wild Shot Range means that a natural roll of 2-9 means that it goes Wild, he'll hit the ghoul on a 7 or better. Thus a natural roll of 7, 8, or 9 are not Wild. A natural 1 always misses. A natural 2, 3, 4, 5, or 6 are Wild.
Let's say Grog rolls a natural 5 - the shot goes Wild and might hit Korg. Korg's AC is 19. Grog rolls a d20 + 2. The +2 is from the magical properties of the longbow. A natural roll of 17 or better hits Korg.
