There is a specific flank trick. Where the AC will attempt to flank a designated target. The down and flee tricks will cause an AC to move out of a damaging zone. The menace trick will cause the AC to threaten a target and only attack if it attempts to leave it's current square.
Otherwise, to get an AC to go to a specific square, it would probably fall under the perform, guard or stay tricks. Depending if you want it to act offensively from that particular square or not.