The ghaeles had focused all of their offense on the beholders, and since their antimagic was a cone, the wounded ones could move out of the surviving beholder's rays, and fled to heal up. The antimagic effect also removed the force walls. The air elementals were not easily visible and could hide in plain sight by not moving so they would retreat skyward to pause for a moment.<br/><br/>The beholders didn't keep popping up as fast as possible, there was often long pauses between each one, long enough for the earth elementals to come back and help disrupt coordinated efforts to counter then with earth gliding, also tossing units into the holes to be sniped by the beholders as they fell.<br/><br/>The kobold trap master was still on his hill when the ghaeles showed up, and waited while they healed and jumped to the mid sized hill to blast and slash for a couple of rounds before jumping back out to their hill, healing up and jumping back to the highest right after the air elementals began pounding the beholders again.