1. Select Units.
2. Click the [LEFT] girl's head first, then click the [RIGHT] girl's head second, located at the command menu bar at the lower right of the screen.
3. Click the Eagle in the center of the two girls. You'll hear the word "OK" as confirmation that the code has been activated.
At the top bar where you can see the date/time, two eagles are located both on the [LEFT] and [RIGHT]:
1. Press the [LEFT] Eagle to Activate God Mode.
2. Press the [RIGHT] Eagle to Skip Level.
You can also reload your ammo by pressing the Armalite located the the command menu bar.