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Investiture of the Horned Devil

(Fiendish Codex II: Tyrants of the Nine Hells)

Transmutation [Evil, Investiture]
Level: Cleric 8, Sorcerer 8, Wizard 8,
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); see text
Spell Resistance: Yes (harmless)

With a flash of red light, you invest the target with infernal energy, drawing power from a horned devil to fuel the spell.
This spell infuses a creature with the terrible essence of a horned devil.
Whenever the subject successfully strikes another living creature with the first melee attack that it makes in a round, the struck creature must succeed on a Will save against the spell's DC or be stunned for 1 round.
In addition, the subject 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 horned 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.