in my game the most notable event that takes place is the discovery of using formic acid as an aerosol spray [chemical shotgun] to kill and mame your enemies.

it give your more technologically advanced ants the ability to fight from a stand off distance from the more primitive stinger equipped ants.

plus i tend to use lots of smaller more numerous ants to disorganize the army ant faction before i send in my heavies [big black carpenter ants]

i usually have a couple of mercenary goliath beetles with queen ant general on top to smash through the enemy formations. with naphta throwing ants in the castle to create havoc.

the combination of my carpenter ant heavies and goliath beetle assault will usually rout the army ant horde.

the army ant invasion attempt takes place around 1200 something and they come on with several big stacks with elite units.