 Going Commando introduces eighteen new weapons , such as the Blitz Gun , Seeker and Lava Gun . Each weapon has a " growth bar " , which increases when the weapon is used to defeat enemies . The weapon is upgraded once the bar is filled , increasing its power and changing the design of it . Certain devices from the original Ratchet & Clank make a return , such as the <unk> , while others are new to Going Commando . The player can use a save file from the original Ratchet & Clank to get " retro " weapons from the first game for free . 
