Vapors - Obscurity
The caster can conjure forth magical vapors, which pour out from around his feet, hands, or just suddenly begin to swirl in the air (caster's discretion). The vapors resemble dense smoke of a color specified by the caster. They fill the area he is occupying in 1 round. The caster can continue to fill areas at a rate of 1 per round until some or all of his area of effect is full. These vapors prevent anyone from seeing the caster, and even radar, sonar, and infrared devices cannot penetrate them. The caster, on the other hand, can see through the vapors perfectly.
The effect that the vapors have on combat is to provide the caster with a +1CS when striking an opponent who is in the vapors and to penalize the opponent with a -2CS for striking at the caster, while the opponent is in the vapors.