Castle Defense

In this game there will be a castle and a road leading to the castle. Enemies will pass through the roads to attack the castle. You lost the game if the castle is destroyed. You need to buy cannons to shoot the enemies to stop them from attacking the castle. When you destroy an enemy, you will get extra money to buy more cannons. When the game progresses, there will be more and more enemies and they will become stronger and stronger. There are a