This code will only work for owners of Spartan Assault Windows 8 edition. Is there any for Xbox 360 edition? Although someone in another thread says that the Flying Colors unlock is a '3 in 1' code, my Draetheus V archive still reads as '1/2' unlocked.
There is a code for the Xbox versions of the game, but you need to obtain the Prodigy, Recruit and Powered by Mjolnir achievements first before you enter it. The code can be found in this video.