Things You'll Need
Instructions
Find a card with a download code inside the package of an unused Prestige or Hardened edition of "Call of Duty: Black Ops." If you already own the normal version of the game, check around to see if you can buy an unused download card separate from the game. If you can't find one, replace your normal version with the Prestige or Hardened edition.
Insert the game disc into your console and install the game, if desired. Enter the download code on the card into the "Redeem Code" option in the main menu.
Wait for the maps to install, and initialize the game. Wait for the main menu to load and select "Zombies." The "World at War" maps are listed, along with the standard "Black Ops" maps.