Become a medieval archer and practice your aiming with a target in the castle. You gotta watch the direction of the wind and hit all your shots. Use your mouse.
Press the trigger without mercy when you have those eggs in sight, aiming at them with the mouse and shooting with the left button of it... Walk with W, A, S, and D.
Avoid that these monsters go inside the fortress, defending and aiming at them with the mouse, and by shooting arrows with the left button of it... You select the power of the shoot according to the time that you keep pressing the button.
Launch the little men with the cannon and get all the coins you see. In upper levels you'll need your intelligence to avoid obstacles and complete your task. Use your mouse.