The USB Host Shield ist used for Shadow MD, Padawan 360 and other controll systems that use a “Console controler”.
It allows to attach the needed Receiver (USB Bluetooth Dongle, XBOX wireless receiver, etc.) to an Arduino 2560.
Please note that you might have to solder some solderspots to run the desired voltage (more info below!)
If the USB Host Shield isn’t working, please check if those 3 solder jumpers are connected. In 99% it’s the issue preventing your USB Host shield from working!