Lower Spell Resistance

(Draconomicon, DnD 3.5)

Transmutation

Level: ; Cleric 4; Sorcerer/Wizard 4
Components: V, S
Casting Time: 1 round
Range: Close (25 ft. + 5 ft./2 levels)
Target: One creature
Duration: 1 minute/level
Saving Throw: Fortitude negates (see text)
Spell Resistance: No

This spell reduces the subject's spell resistance by 1 per caster level (maximum reduction 15).
This reduction can't lower a target's spell resistance below 0.
The target of the spell takes a penalty on its saving throw equal to your caster level.