Astral Combat (Proficiency)

In the unique arena that is the Astral, combat takes on a new perspective. Attacks come from any of the three dimensions, weapons carry little mass, and blows are driven by the force of Intelligence rather than Strength. Those able to adapt to these conditions gain a considerable advantage over their foes.
Much like the blindfighting proficiency gives those who've mastered it an edge in the darkness, astral combat lets a body fight on the Astral without disability. Those who use this skill have no penalty for firing missile weapons. Foes of the character gain no benefit for higher position, but the trained astral combatant can make a successful proficiency check to gain such a position over his opponent just in time to strike with a +1 bonus. (See "Mindwar: Astral Combat." )
==From Sage Advice (Dragon #254)==
Note that Astral combat requires a roll only if the character tries to maneuver for advantage. Most of the time, the skill simply negates the normal penalties for Astral combat (-2 to missile attacks). Likewise, Astral running boosts the character's movement rate in the Astral Plane to six times his Intelligence score (maximum of 96).