Siege weapons can destroy buildings, but are weak against other units, especially cavalry. Greeks can also use Petroboli to defeat enemy ships.

The catapult most common in the ancient age was a traction catapult called a Petrobolos (literally "stone thrower") by the Greeks. The power of the arm was generated by traction, usually by pulling or winding down a balanced throwing arm. The best Petrobolos of the age threw stones weighing around 125 pounds. Rocks of this weight plunging down walls and buildings were capable of devastating damage.