Acquire Winged Back Part Easily How to unlock: Complete normal mode to unlock hard mode and mission select. Create an AC with as much defense as possible and equip both arm weapons with the Motorcobra machine guns. You can obtain the machine guns can by beating one of the simulation missions in the schematic menu. Select the mission where you fight four Nexts at once. Quickly defeat the first Next that comes at you, after that you can defeat the other Nexts easily.
Hard Mode -Armored Core 4 How to unlock: Beat a chapter to access hard mode.