Reaching across the planes, you form a momentary link between yourself and the Negative Energy Plane. Drawing on your temporary stygian channel, you discharge a power bolt that extends from your outstretched hand. Anyone caught in the area gains a 1d4 negative levels. This is a negative energy effect.
If the subject has at least as many negative levels as it has Hit Dice, it dies. Assuming the subject survives, it regains lost levels after a number of hours equal to your manifester level (maximum 15 hours). Negative levels usually have a chance of permanently draining the victim's levels, but the negative levels from stygian bolt don't last long enough to do so.
Undead affected by a stygian bolt gain 2d4×5 temporary hit points that last for up to 1 hour.
For every 4 additional power points you spend, the power bestows an additional 1d4 negative levels, and affected undead gain 2d4×5 additional temporary hit points.