How about this special rule for the inquisitors:
Exterminatus: once per game, an inquisitor can have the orbiting space ships fire thier main guns at MAXIMUM firepower! Remove the inquisiton group from play immedaitly as they have teleported back to the battleship in order to avoid the impending doom. Pick any point on the battlefield and place a marker there. the marker deviates 3d6 inches, even if a hit is rolled. everything w/ in 5d6 inches of the marker suffers a Str;D ap1 hit.
sorry, i just love stuff that goes BOOOM!
