You are one a mission to kill the all the enemies who are trying to enter your country. Go find the enemies using minimap and kill them before they attack you. Earn points and money by killing the enemies in the given time, Also you can buy new upgrades with the earned money.
Arrow Keys Or W,A,S,D to move. Shoot with the mouse. Press Space bar to swap weapons.
A context menu should be shown when right-clicking or, on touch devices, long-pressing in the game. This menu especially allows to play in full screen and control the volume.