I also have no idea how to use chariots; I tried some methods stated before such as driving them through an enemy formation and flooding the holes left there by the chariots with other infantry but what happened was that the chariots drives towards enemy formation, starts peppering the enemy with javelins, until the front of the chariot's formation somehow engages in combat with the enemy, losing around 10 men. so I started spam-clicking for the chariots to move instead of fight, and the clumsiness of the chariots made them lose another dozen men, while I kept swearing at the computer. then the chariot finally moves through the enemy formation, holes appear, I order some botroas forward fill the holes; however the melee does not seem to be going well for my troops, so I moved the cidanh a short distance away and order them to turn and charge (the moving away was to make distance and gather momentum for the charge). however the charge did nothing useful and the enemy units at the back of their line turn around and lower the number of men in my chariots to 14.

which is why I stopped playing my Casse campaign. A pity though, Barae was a really powerful character.