My reacent tactics for Seleucids.Works with both on offence and defence.Form up a pike wall.hit enemy to the both flanks with your elephants.Simultaneously move your Cavalry behind the enemy.Its beutifull to watch but make sure not to deploy your infantry too close to the enemy.Just let your Elephants do the work.those units that try to move forvards,destroy them with concentrated missile fire.And those who try to retreat or run,kill them with your cavalry.