Hi there, once again we have a code for XP in Halo 4. With this code you get 50,000 XP and the LASO Emblem for Halo 4.
Unfortunately this one comes with a catch, you must complete the campaign on Legendary with All Skulls On. You can do this in Co-Op, which would and will be much easier on your blood pressure.
You can enter the code via the Xbox and launching Halo Waypoint and entering the classified section or you can enter the code on your computer here (much easier)
Here’s a guide on how to enter the code to earn the unlocks, provided you meet the requirements.