Inverted Magic

Note: This spell first appeared in the Hellbound: The Blood War boxed set, and were designed for fiendish spellcasters. DMs must give specific permission for PCs to have access to these lower-planar dweomers.

This powerful offensive spell only affects creatures that have some level of natural magic resistance. Inverted magic turns that protection against them.

When the caster touches the intended target, he unleashes - and inverts - the inherent magical power within the creature. The target can attempt a saving throw and a magic resistance roll to avoid the effects. If it fails the save, the creature is racked with painful energy and suffers a percentage of its current hit points in damage equal to its magic resistance. What's more, the sod is stunned for a number of rounds equal to the number of hit points lost divided by 10 (round down). When stunned, a creature can make no attacks, use no spells or magical abilities, and moves at half speed. The stunned creature's opponents receive a +4 bonus to attack rolls.

For example, a babau (with 5O% magic resistance) fights with a mortal priest until it has only 40 hit points left. The priest then casts inverted magic on the fiend. The babau fails its saving throw and loses 5O% of its remaining hit points, bringing it to 20. In addition, the babau is stunned for two (20 divided by 10) rounds.

Another example: A black abishai (3O% magic resistance) has 20 hit points left in a scrap with a priest. The priest casts inverted magic on the abishai, which fails its save and loses 30% of its remaining hit points, bringing it to 14. The abishai lost only 6 hit points, so it's not stunned at all (6 divided by 10, rounded down, is less than one).

The material component for the inverted magic spell is a silver holy (or unholy) symbol worth at least 100 gp. The symbol is consumed by the magic unleashed.