The Iron Age equivalent of the Bronze Age Stone Thrower or the Early Middle Ages Catapult, a artillery unit. Having attack bonus on hills and effective against heavy class units, such as Legionnaire. It has improved attack range and attack value over the BA stone thrower however, it is vulnerable to any attack due to its low defense.
It can be used as fire support by staying behind the army. It is possible using full group of Ballistas to combat, it would be effective against both melee classes but vulnerable if enemies contain cavalry, such as Mounted Warriors.
Ballista with Legionnaire