Economy Mode is a mode where you spawn with a pistol and survive waves of balls, while shooting the balls to get money. With that money, you can buy health, ammo, and weapons.
Buying Guns In Economy You start with a pistol and $0. Each ball you shoot will give you $100. You can see your money in the top right corner of your screen. Also when you want to buy something , you must first have enough money, and press the key corresponding with that item. For example, if you want to buy health, you will need $500 and press the f1 key. Once your purchase is complete, the item will spawn in front of you to pick up.