The CIO Armor my favorite unlockable armor set in Halo 4 so far.
This armor set is unlocked with the commendation Spartan Slayer – Master.
The only other option to get the CIO Armor set is if you pre-ordered Halo 4 through Amazon, which would not only give you this armor, but also the Web Skin for it.
You might be able to find a code for C.I.O. Web Armor on ebay. At the time of writing this article, there are a lot of codes currently for sale.
Check out my other guide for the complete list of unlockable armor sets in Halo 4.
Below is the CIO Armor with the Web skin on it.
Check out my list of unlockable armor sets in Halo 4 if you’re looking for more armor sets to unlock.