If the game freezes, just click inside it (games can get unresponsive if you click elsewhere on the page).
This is a tower defense game. Place guns along the path to kill the enemies as they come.
Place your guns around the map and see how long you can survive. There ar 15 levels.
Keep an eye on Flights. When it passes trough it drops the bombs over the guns.
Use your mouse to place the guns.