Phalanxs in a line supported with counter assault units and slingers to the rear. A general with a cav unit or two is good for running down fleeing units.

Be static until the majority of your missiles run out.

Cheesy method:

Camp in the corner.

*
*P
*OP
*OAP
*OHAP
*OOHAP
*OOGHAP
*OOOOOOP
************

Slightly weight the counter assault units to the right flank as it may break first.

Good idea to have overlapping alternate versions of phalanxs

Out on the plain being brave form a square or horseshoe out of the phalanxs and have assault units for support