Purchased a Gold REQ Pack.
From the main menu press
to open the Spartan Hub.
Purchase a Gold Pack
for 10,000 REQ Points
, or from the XBL Store ($2.99 USD). You start with 7,500 REQ Points, and earn 700 or more per match. It won't take long to get to 10,000, so save your money. Once you have purchased one it will be opened automatically.
The achievement description is wrong as you will not get this achievement by opening a Gold Pack from the Open Packs
screen, such as the one included in the Warzone REQ Bundle
, so Buggy -