New codes from Major Nelson:
Marcus Fenix Papercraft
http://www.xboxcogcodes.com/?code=4Z7UYFCWR8GD
OG Slick Wallpaper Graffiti 2
http://www.xboxcogcodes.com/?code=8MUDVEX37KYG
Silverback Schematic Wallpaper
http://www.xboxcogcodes.com/?code=6GWR4T9HBPAN
Source