- Draft Horses increases speed by 20%.
- Engineers increases attack by 25%, doubles damage against walls and increases range by 2.
Petroboli are the only ranged siege weapons available during the Heroic Age. This gives the Greeks the advantage of assaulting an enemy town from a distance, up to 28 meters. They are similar to the Catapult but do less damage, throwing multiple small rocks at once. Petroboli are naturally strong against buildings and have a large bonus against ships. They also do moderate damage to regular soldiers due to their pierce attack. However most units can dodge the projectiles with ease and like all siege weapons, Petroboli should always have an escort.
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 the walls and buildings were capable of devastating damage.
- The Petrobolos shares the same icon as the Egyptian Catapult.
- If the Petrobolos is targeting a building and there are other buildings separating the two, some of its projectiles will strike the buildings in between the two instead.