~~ Steps ~~
Step 1. Plug Your USB into your xbox 360

Step 2. Go To system, storage, hard drive, gaming and apps, call of duty black ops

step 3. delete Title update #11 or whatever the title update is

Step 4. Clear System Cache

Step 5. Go To system, storage, then find the gamer profile you wish to mod, then click on it and move it to your USB

Step 6. Open Horizon, it should have detected your device (USB)

Step 7. double click flash drive, double click gamer profiles.

Step 8. Right click your gamer profile and press extract, and extract it to desktop

Step 9. drag & drop the file you just extracted to your desktop into horizon

Step 10. Your gamer profile should appear on the horizon program, click Contents

Step 11. Go To The File what says 41560855.gpd, right click and then press Replace

Step 12. Browse your computer for your modded GPD File, the link for that is below the steps.

Step 13. Double click your modded gpd file when you have found it

Step 14. it should say file replaced successfully, now just click Save, rehash and resign.

step 15. now delete the gamer profile which is currently in horizon, on gamer profiles

step 16. drag & drop the one you have just modded into gamer profiles

Step 17. Unplug usb and insert into xbox, now just transfer your gamer profile onto your xbox and enjoy your modded zombies!

This is for educational purposes only!
It will not work online so dont try it, unplug your internet cable and play it offline.

Modded GPD - [ Register or Signin to view external links. ]
Horizon - [ Register or Signin to view external links. ]