Siege weapons can destroy buildings, but are weak against other units, especially cavalry. Ballistas can be used by the Norse to defeat ships.

The Ballista was another type of pre-gunpowder era artillery, mainly used against men in formation. It was a large bow mounted sideways. It used a winch and ratchet to create bow tension. The missile was usually a large metal, or metal-headed, bolt. Fired into a mass of men at ranges up to 1000 feet, bolts could disable several enemies. Ballistas could be placed on fixed mounts on walls or ships, or mobile-wheeled mounts for battlefield use. They were not particularly effective against fortified buildings and walls.