Darkness

This is related to the spell effect DO NOT USE - Darkness

The spell-effect darkens the area around the effected actor a bit and adds a black-light effect on the actor that makes him appear almost completely black.

This actor-value corresponds to the magnitude of the Darkness-effect, i.e. the size of the area that is darkened by the effect (this seems to work only in exteriors, and a changed magnitude only applies on a cell-change).