If I cast "Disrupting Weapon" on a +3 Greatsword and I attack an incorperal creature (A ghost) How many times do I have to roll a 50% miss-chance ? Before I have the creature roll a will save to avoid distruction ?
There is no miss chance when attacking an incorporeal creature. Incorporeal creatures ignore all nonmagical damage, and ignore half of any magical damage they take. You just simply cut the damage dealt in half.
So a +3 greatsword deals 2d6+3 damage per hit (just loking at the weapon itself with no other modifiers). Against an incorporeal creature, you roll to hit normally, and if you do hit you deal (2d6+3)/2 damage.
Technically, it's not a miss chance -- just a 50% chance for the spell effect to be ignored.
The creature gets a chance to ignore the effect every time you strike it. I don't think it really matters whether you roll the percentile first or the creature makes their saving throw first. I'd suggest rolling the percentile first so the GM doesn't have to look up the creature's saving throw bonus when the effect would have been negated anyway.
If I cast "Disrupting Weapon" on a +3 Greatsword and I attack an incorperal creature (A ghost) How many times do I have to roll a 50% miss-chance ? Before I have the creature roll a will save to avoid distruction ?There is no miss chance when attacking an incorporeal creature. Incorporeal creatures ignore all nonmagical damage, and ignore half of any magical damage they take. You just simply cut the damage dealt in half.
So a +3 greatsword deals 2d6+3 damage per hit (just loking at the weapon itself with no other modifiers). Against an incorporeal creature, you roll to hit normally, and if you do hit you deal (2d6+3)/2 damage.
He's talking about the fact that incorporeal creatures have 50% chance to ignore corporeal non-force spell effects that don't deal damage.
I think his issue is actually with the disrupting weapon spell.
Incorporeal (Ex) An incorporeal creature has no physical body. It can be harmed only by other incorporeal creatures, magic weapons or creatures that strike as magic weapons, and spells, spell-like abilities, or supernatural abilities. It is immune to all nonmagical attack forms. Even when hit by spells or magic weapons, it takes only half damage from a corporeal source (except for channel energy). Although it is not a magical attack, holy water can affect incorporeal undead. Corporeal spells and effects that do not cause damage only have a 50% chance of affecting an incorporeal creature. Force spells and effects, such as from a magic missile, affect an incorporeal creature normally.
That would still have no miss chance. It is part of the weapon attack itself, and wouldn't be subject to the 50% chance to fail. The spell isn't trying to affect the undead at all - it changes the weapon itself.
Something like command undead would have that chance to fail, however.