Play through the 10 mission campaign, with beautifully illustrated graphic novel style story panels. Missions range from offence to defence missions- upon which you can build a base to stop the alien horde.
There is also a survival mode with 6 maps, where you destroy wave after wave of incoming aliens.
Earn in-game money with every battle you fight, or every achievement you earn. You can spend on upgrading your weapons by buying different components. There are 7 different upgradable parts, this means you can completely customize your gun and armour to suit your style of play.
There are over 70 different items and components in the game with which to do this; including 17 core weapons which range from standard rifles to flame-throwers and rocket launchers: Make a fast firing sniper rifle with exploding rounds, or a deadly powerful shotgun with a bayonet for close encounters!