When you log in the game, you will find yourself in the garage, where you can assemble your own deadly creations.
If you're playing for the first time, you will find there Rusty – a pre-assembled fighter that you can use to immediately enter battle. Or, you can stick around and explore the Garage and the Workbench, to customize a robot of your own.
You start with 3 available robot slots in the Garage. Should you find them insufficient, you can purchase additional slots with the Credits you earn, or you can just disassemble one of your old robots. To disassemble a robot, just select its Chassis and Right-click it.