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Investiture of the Barbed Devil

(Fiendish Codex II: Tyrants of the Nine Hells)

Transmutation [Evil, Investiture]
Level: Blackguard 4, Cleric 6, Sorcerer 6, Wizard 6,
Components: V, S, M,
Casting Time: 1 standard action
Range: Close (25 ft. + 5 ft./2 levels)
Target: One living creature
Duration: 1 minute/level
Saving Throw: Will negates (harmless)
Spell Resistance: Yes (harmless)

With brisk arcane gestures that glow with a fiery red light, you imbue a target with the might of a barbed devil, causing long thorns to sprout all over its body.
You cause the target of this spell to grow a number of long barbs similar to those found on a barbed devil.
While under the effect of the spell, the target does not provoke attacks of opportunity when initiating a grapple.
If the subject already has improved grab or the Improved Grapple feat, it instead gains a +4 profane bonus on grapple checks.
Whenever the subject successfully makes a grapple check to grab a foe, pin a foe, or deal damage, it impales its foe on its barbs, dealing extra damage based on its size.
The subject also gains resistance to fire 10.
This resistance stacks with the resistance granted by other evil investiture spells (but not with multiple castings of investiture of the barbed devil).
While this spell is in effect, magic weapons with the evil outsider bane special ability have full effect against the subject of the investiture.
After the spell's duration expires (or if it is dispelled or ended through some other means), the subject is fatigued for 1 minute.
Material Component: A fist-sized chunk of brimstone.

Size Damage
Tiny or smaller 1d8
Small 2d8
Medium 3d8
Large 4d8
Huge 5d8
Gargantuan 6d8
Colossal 7d8