Combat Maneuvers/Bull Rush
Action: standard action or as part of a charge in place of the melee attack
Target: one opponent who is no more than one size category larger than you.
Attack of Opportunity: yes
Feats: Powerful Maneuvers, Greater Bull Rush
A bull rush attempts to push an opponent straight back without doing any harm. If your attack is successful, your target is pushed back 5 feet. For every 5 by which your attack exceeds your opponent’s CMD you can push the target back an additional 5 feet. You can move with the target if you wish but you must have the available movement to do so. If your attack fails, your movement ends in front of the target.
An enemy being moved by a bull rush does not provoke an attack of opportunity because of the movement unless you possess the Greater Bull Rush feat.
You cannot bull rush a creature into a square that is occupied by a solid object or obstacle.
If there is another creature in the way of your bull rush, you must immediately make a combat maneuver check to bull rush that creature. You take a –4 penalty on this check for each creature being pushed beyond the first. If you are successful, you can continue to push the creatures a distance equal to the lesser result.