Fiendish Gloom Graft

Species Graft

As the descendants of fiendish beings, tieflings can cloak an area in an almost unholy darkness. With thousands of gravitonic light-dampening cells embedded under your dermal layer, you can also weave a similar gloom. As a standard action, you can cause light within 20 feet of you to decrease one step. This lasts for 1 minute, but you 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 your level. You can use this ability once per day, plus a number of additional times equal to half your level.