Spurn the Supernatural

(Tome of Magic)

Level: Bard 4, Cleric 5, Druid 5, Sorcerer 5, Wizard 5,
Components: V, S, TN,
Casting Time: 1 standard action
Range: Close (25 ft. + 5 ft./2 levels)
Target: One creature
Duration: Concentration, up to 1 round/level
Saving Throw: Fortitude negates
Spell Resistance: Yes

Your make your hand into a grasping claw as you speak your foe's truename, stealing some of its supernatural energy, which appears as a minuscule storm-cloud in your hand.
With this spell, you can temporarily suppress a supernatural ability possessed by the target creature.
For the duration of the spell, the target is unable to activate the supernatural ability you have chosen.
Extraordinary and spell-like abilities aren't affected by this spell.
If you succeed on the Truespeak check, you can suppress one of the creature's supernatural abilities, plus another supernatural ability for every 5 points by which your result beat the Truespeak DC.
Truename Component: When you cast this spell, you must correctly speak the personal truename of the creature you're targeting.