2 Added information on Transdimensional Spell
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2. He may hit. The DM checks the shadow's 50% immunity to corporeal damage sources and, if Abel successfully overcomes that, then the shadow makes a Willpower saving throw. Because the attack is magic yet delivered by a corporeal source, the shadow's incorporeal subtype's 50% immunity to corporeal damage sources must be checked.


The only instances in which you don't check for the immunity to corporeal damage are Ghost touch weapons, Positive energy spells, Negative energy spells, and Force effects. All spells that don't fit into those three categories must roll to see if the spell takes effect on the target.

The key part of the paragraphs above is the following:

"Even when hit by spells or magic weapons, it 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)."

Since your spell is a Necromantic effect but doesn't state whether or not the spells is a positive or negative energy effect in its description, you must roll to see if the spell takes effect on the incorporeal creature.

Transdimensional Spell

Based on the Rules as written effect for the Feat Transdimensional spell, any spell aside from the above listed effects has a 50% chance to fail on creatures if they are on the ethereal plane. However, this 50% miss chance can be bypassed by the feat Transdimensional spell.

Transdimensional Spell ( Complete Arcane, p. 84)

[Metamagic]

You can cast spells that affect targets lurking in coexistent planes and extradimensional spaces whose entrances fall within the spell's area. Prerequisite

Benefit

A transdimensional spell has its full normal effect on incorporeal creatures, creatures on the Ethereal Plane or the Plane of Shadow, and creatures within an extradimensional space in the spell's area. Such creatures include ethereal creatures, creatures that are blinking or shadow walking, manifested ghosts, and creatures within the extradimensional space of a rope trick, portable hole, or familiar pocket (see page 106). You must be able to perceive a creature to target it with a transdimensional spell, but you do not need to perceive a creature to catch it in the area of a burst, cone, emanation, or spread. A transdimensional spell uses up a spell slot one level higher than the spell's actual level.

Normal

Only force spells and effects can affect ethereal creatures, and no Material Plane attack affects creatures on the Plane of Shadow or in an enclosed extradimensional space. There is a 50% chance that any spell other than a force effect fails against an incorporeal creature.

2. He may hit. The DM checks the shadow's 50% immunity to corporeal damage sources and, if Abel successfully overcomes that, then the shadow makes a Willpower saving throw. Because the attack is magic yet delivered by a corporeal source, the shadow's incorporeal subtype's 50% immunity to corporeal damage sources must be checked.


The only instances in which you don't check for the immunity to corporeal damage are Ghost touch weapons, Positive energy spells, Negative energy spells, and Force effects. All spells that don't fit into those three categories must roll to see if the spell takes effect on the target.

The key part of the paragraphs above is the following:

"Even when hit by spells or magic weapons, it 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)."

Since your spell is a Necromantic effect but doesn't state whether or not the spells is a positive or negative energy effect in its description, you must roll to see if the spell takes effect on the incorporeal creature.

2. He may hit. The DM checks the shadow's 50% immunity to corporeal damage sources and, if Abel successfully overcomes that, then the shadow makes a Willpower saving throw. Because the attack is magic yet delivered by a corporeal source, the shadow's incorporeal subtype's 50% immunity to corporeal damage sources must be checked.


The only instances in which you don't check for the immunity to corporeal damage are Ghost touch weapons, Positive energy spells, Negative energy spells, and Force effects. All spells that don't fit into those three categories must roll to see if the spell takes effect on the target.

The key part of the paragraphs above is the following:

"Even when hit by spells or magic weapons, it 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)."

Since your spell is a Necromantic effect but doesn't state whether or not the spells is a positive or negative energy effect in its description, you must roll to see if the spell takes effect on the incorporeal creature.

Transdimensional Spell

Based on the Rules as written effect for the Feat Transdimensional spell, any spell aside from the above listed effects has a 50% chance to fail on creatures if they are on the ethereal plane. However, this 50% miss chance can be bypassed by the feat Transdimensional spell.

Transdimensional Spell ( Complete Arcane, p. 84)

[Metamagic]

You can cast spells that affect targets lurking in coexistent planes and extradimensional spaces whose entrances fall within the spell's area. Prerequisite

Benefit

A transdimensional spell has its full normal effect on incorporeal creatures, creatures on the Ethereal Plane or the Plane of Shadow, and creatures within an extradimensional space in the spell's area. Such creatures include ethereal creatures, creatures that are blinking or shadow walking, manifested ghosts, and creatures within the extradimensional space of a rope trick, portable hole, or familiar pocket (see page 106). You must be able to perceive a creature to target it with a transdimensional spell, but you do not need to perceive a creature to catch it in the area of a burst, cone, emanation, or spread. A transdimensional spell uses up a spell slot one level higher than the spell's actual level.

Normal

Only force spells and effects can affect ethereal creatures, and no Material Plane attack affects creatures on the Plane of Shadow or in an enclosed extradimensional space. There is a 50% chance that any spell other than a force effect fails against an incorporeal creature.

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2. He may hit. The DM checks the shadow's 50% immunity to corporeal damage sources and, if Abel successfully overcomes that, then the shadow makes a Willpower saving throw. Because the attack is magic yet delivered by a corporeal source, the shadow's incorporeal subtype's 50% immunity to corporeal damage sources must be checked.


The only instances in which you don't check for the immunity to corporeal damage are Ghost touch weapons, Positive energy spells, Negative energy spells, and Force effects. All spells that don't fit into those three categories must roll to see if the spell takes effect on the target.

The key part of the paragraphs above is the following:

"Even when hit by spells or magic weapons, it 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)."

Since your spell is a Necromantic effect but doesn't state whether or not the spells is a positive or negative energy effect in its description, you must roll to see if the spell takes effect on the incorporeal creature.