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Investiture of the Ice Devil

(Fiendish Codex II: Tyrants of the Nine Hells)

Transmutation [Evil, Investiture]
Level: Cleric 7, Sorcerer 7, Wizard 7,
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)

Malevolent blue light suffuses the target as the temperature nearby drops ominously.
You infuse a creature with the savage brutality and cold cunning of an ice devil.
While under the effect of this spell, whenever the subject hits a living creature with a melee attack, that creature must succeed on a Will save against the spell's DC or be slowed for 3 rounds.
The subject also deals an extra 1d6 points of cold damage with each successful melee attack that it makes with a weapon or natural weapon.
In addition, the subject gains resistance to cold and fire 10.
The resistance to fire stacks with the resistance granted by other evil investiture spells (but not with multiple castings of investiture of the ice 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.