Tiefling

As a standard action, the tiefling causes light within 20 feet of her to decrease one step. This gloom lasts for up to 1 minute, but the tiefling can dismiss it as a swift action. Nonmagical light sources can’t increase the light level in this area. Magical light can increase the light level in this area only if it’s from an item or creature of a level or CR higher than that of the tiefling. A tiefling can use this ability once per day, plus a number of times equal to half her CR or level.