Pila vs Charge...

[RLucid]

In the situation where Barbs will charge, then in general try and use terrain and cavalry to tire them, before the main clash, as well as have them softened up by missile units, who are very effective against poorly armoured Barbarian troops.

In general I've found using retreat of frontline velites skirmishers to time the pila volley an effective tactic, the infantry then engage opponents who may be chasing skirmishers, and therefore not receive charge bonuses. Sometimes, I'm able to get off 1st pila volley, and then order a counter-charge, as tired troops climb slowly.

Further javellin / pila fire from non-frontline forces can also quickly push Barbarian units into routing, especially when concentrated against victim units, who can be outflanked, and thus rapidly trigger a mass rout of enemy.

[Chloe]

I always try to time the pila throw to during the warcry, so that it does maximum damage. I killed 20 or so men in one pilum throw this way.