Catapults are built from a Workshop that is Level 5 or higher. They are the slowest unit in the game but also do the best damage to buildings.
Catapults are the best at destroying Structures, but they're easy to see because of their extremely slow speed, they will slow any army to their movespeed. Catapults are also very strong at destroying Helepolis which can otherwise be difficult to attack due to their protected position in enemy formations.
|Training Ground||Fighter · Bowman|
|Barracks||Swordsman · Archer · Hoplite · Gladiator|
|Stable||Cavalry · Knight|
|Workshop||Helepolis · Catapult|
|Trading Post||Ox Wagon|
Catapults can rapidly demolish Stronghold gates in conjunction with the Stronghold Gate Offensive Boost technology available from the University. Tribes will sometimes choose to place new cities near contested strongholds with the intent of building a large number of catapults to be able to quickly threaten the stronghold in question whenever another tribe takes it.
All unit stats by level can be viewed at the Official Help Database