I previously asked this question in regards to the asymmetry between corporeals attacking incorporeals (having a miss chance of 50%) and incorporeals attacking corporeals (no miss chance) as per the Monster Manual I and d20srd.org.
KRyan's answer to my question suggested following the updated incorporeal rules published in the Monster Manual III ("the updated version is also reprinted in Rules Compendium and Tome of Battle, and possibly elsewhere").
In this updated version (Monster Manual III, page 214), I observed an asymmetry: incorporeal creatures have no miss chance of hitting a corporeal with a spell, whereas corporeals do have a miss chance against incorporeals. Hence, it appears that this rule would favour incorporeals during a fight (wether they were an incorporeal monster or a Spellcaster PG or PNG that made themselves incorporeal in some way as described in my comment here).
The updated rules state, in part:
Even when hit by spells, including touch spells, or magic weapons, [an incorporeal creature has a 50% chance to ignore any damage from a corporeal source (except for positive energy, negative energy, force effects such as magic missile, or attacks made with ghost touch weapons). [...] Magic items possessed by an incorporeal creature work normally with respect to their effects on the creature or on another target. Similarly, spells cast by an incorporeal creature affect corporeal creatures normally.
What would be the implications of making this rule symmetrical? I see two possible ways to do so:
- Changing the first part, so that corporeal creatures have no miss chance when trying to hit an incorporeal with a spell.
- Changing the second part, so that incorporeal creatures also have a 50% chance of missing corporeal creatures with a spell.