how do "miss chance" abilities stack/overlap?

[Particle_Man]

Lets say I have a Hexblade with Aura of Unluck, and the spell Entropic Warding. Assume some item gives him the blur ability. If all three are active on him at the same time, then what is the miss chance for ranged attacks? For meelee attacks?

While I am here, does Touch of Idiocy stack with other castings of Touch of Idiocy?

 

[MichaelH]

Lets say I have a Hexblade with Aura of Unluck, and the spell Entropic Warding. Assume some item gives him the blur ability. If all three are active on him at the same time, then what is the miss chance for ranged attacks? For meelee attacks?

Aura of Unluck and Blur both give him a 20% miss chance. I am not familiar with Entropic Warding, but assuming it also provides a 20% miss chance, your character benefits from a 20% miss chance against ranged and melee attacks. The miss chances do not stack (PH 152).

While I am here, does Touch of Idiocy stack with other castings of Touch of Idiocy?

No. The spell does not do ability damage to its target, which would stack. It gives the target a penalty to its ability scores. Penalties do not stack. This spell works like Ray of Enfeeblement. So if you cast this spell and roll a 1, then you cast it again and get a 6, the penalty is 6 not 7.

 

[Infiniti2000]

The miss chances do not stack (PH 152).

Concealment miss chances don't stack. There's no rule that miss chances in general don't stack. For example, an invisible and incorporeal creature would apply both his concealment miss chance and then his incorporeal miss chance, separately.

 

[gnfnrf]

Lets say I have a Hexblade with Aura of Unluck, and the spell Entropic Warding. Assume some item gives him the blur ability. If all three are active on him at the same time, then what is the miss chance for ranged attacks? For meelee attacks?

Miss chances never stack (that is, accumulate). They either overlap or act independently.

So for a melee attack, there are two 20% miss chances. One that the aura of unluck causes misfortune, and one that the blurriness causes the attacker to miss. Roll both of these separately.

Against a ranged attack, there are three 20% miss chances. There could be misfortune, the entropic shield could deflect the shot, and the target might be too blurry.

Doing this is NOT the same as having a 40% or 60% miss chance.

In some cases, multiple miss chances clearly do not apply. The rules state that multiple incidents of concealment do not operate independently (that doesn't apply here, since only blur actually offers concealment).

Also, non-concealment visual effects (such as displacement) should not stack with actual total concealment (from, say, the attacker being blind). This isn't spelled out anywhere that I know of, but common sense should apply.

Where common sense starts to struggle is blink, since the miss chance is partly physical and partly visual. But, you didn't ask about that.

--
gnfnrf

 

[Sejs]

While I am here, does Touch of Idiocy stack with other castings of Touch of Idiocy?

Nope. Touch of Idiocy applies a penalty. The highest penalty would apply. So if you get a 3 on your 1d6, and the other caster gets a 5, the target would take the -5.

 

[Hypersmurf]

Concealment miss chances don't stack. There's no rule that miss chances in general don't stack. For example, an invisible and incorporeal creature would apply both his concealment miss chance and then his incorporeal miss chance, separately.

Incorporeality doesn't apply a miss chance; it applies a chance to ignore damage. So the two are completely unrelated.

-Hyp.

 

[Drowbane]

Incorporeality doesn't apply a miss chance; it applies a chance to ignore damage. So the two are completely unrelated.

-Hyp.

(o.0)

huh, good to know

 

[Particle_Man]

I wonder how many of these "percentage to not take damage" effects are out there, that do not provide a simple bonus to armor class or penalty to opponents' attack rolls.