The Roman Legion is the army that Caesar commands. It is better funded, more organized, and advanced than the Gallic Tribes in game, which use brute force melee tactics to get their revenge on the Romans.
Other(not a Roman unit)Edit
Use ranged units to overwhelm the enemy.
Counter: if you're playing as the Gaul, don't let this occur too heavily; if it does, use behemoths and high damage units to break through if possible and needed, otherwise you will need to make sure the base has enough archers and that you are ready to counter-attack.