This unit can destroy buildings.

Catapults are most effectively used later in the game to target an opponent's farm. This is because farm levels are costly to build and take a long time to upgrade. When you lower the level of the opponents farm, this forces them to first rebuild their farm before doing anything else since they do not have enough population to build anything with. Since the farm take such a long time to rebuild you will likely either have nobled the target or have cleared all his troops. This tactic can prove to backfire on you since when you noble the village you will have to rebuild the farm ny yourself before doing anything else. This will leave you vunerable to enemy attack.