fumbles in combat?

[CalrinAlshaw]

The one my group uses is pretty simple...

If you roll a natural 1 (one) make a reflex save against DC 15.
If you fail your reflex save you lose the grip on your weapon and it thrown from your hand roll d8 to see which direction and d6+4 to see how many feet it was thrown.
If you succeed on the saving throw then you recover from the miss as if from a normal attack that misses.
If you roll a natural 1 (one) on the reflex save, something bad happens.

Examples:
Bowstring breaks, you must spend 1 move action retrieving a spare, and one full-round action replacing the old.
Weapon flies from hand and hits the ground taking 1d4 damage (not negated for hardness).

Just as simple examples. Often changed depending on where we are and the situations.

Calrin Alshaw

 

[Bendris Noulg]

I like it nice and easy...

Roll a 1, you threaten a fumble.

Roll again; if the roll's a miss, you open yourself up to an Attack of Opportunity.

If using a ranged weapon, I roll scatter-dice to determine the direction of the projectile, ignoring clearly silly results (like behind you); getting hit by "friendly fire" is common enough to, well, be called "friendly fire", so it makes sense to account for it.