When you are hiding and use a swift action on your turn to aid an ally in making a menacing chant, you can cast any harmful mind-affecting spell that you know against an enemy and use the chant as part of your casting. Immediately upon casting the spell, you make a Stealth check with a +20 bonus to Hide your location from any enemies. Any verbal and somatic components that are part of the spell become part of the chant and any enemy that is unable to determine your location is unable to identify the spell using Spellcraft.

Fixed it
Changed it.