There appear to have been two grades of elephant used in ancient battles; Firstly there were what I'll call 'war elephants', for want of a better term, that were fully trained for the rigours of battle and appear to have been quite reliable (for an elephant at least). However, elephants of this type were both rare and extremely expensive, and because of this on a number of occassions ancient generals used only partially trained elephants in there battles instead. The most notable example of the use of the second kind were the Cartheginian elephants at Zama, which were poorly trained and quickly ran away. I've therefore come up with these rules that allows players to pick what grade of elephant they want to use - cheap and cheerful or expensive and reliable.
The elephants included in the army lists are assumed to be well trained and (fairly) reliable war elephants. A player may choose to take poorly trained elephants if he prefers, but they are much more liable to panic. Halve the total points cost (i.e. including crew and upgrades) of a poorly trained elephant, rounding fractions up.
Poorly trained elephants were prone to panic, and this was often explopited by an opponent. To reflect such tactics, if your oppoent has included poorly trained elephants in his army then you are allowed to use a 'scare tactic' once per battle. The scare tactic is announced at the start of the turn when charges would normally be declared (it doesn't make any actual game difference as to what the tactic is, but in the interests of fun it is highly recommended that the player invents his own, suitably outlandish tactic, before roll any dice!).
At the time that the tactic is used 3D6 are rolled. Any and all poorly trained elephants within that many inches of an enemy standard bearer or musician who is on foot must pass a ld test or stampede (note that mounted standard bearers and musicians can't be used for scare tactics). An army that uses a scare tactic may move and shoot normally during the same turn, but may not declare any charges or make any march moves (basically, the army stands around and watches to see what effect the scare tactic had!).