Guns Up!

Guns Up is split into defense and offense. The player spends currency (in this case, munitions) to build up a base and its defenses or to attack other players. As the player levels up, more classes, defenses, and abilities are unlocked. Gold, the second in-game currency, is earned slowly through leveling or by real-world purchases, and allows the player to build defenses or gain offensive capabilities in a faster manner.

Alternately, the player can take on missions and an endless survival mode. Both require the player to be at a certain level to unlock.