1. "Kino Der Toten" - First Map is given to you. Just access it through the main menu.
Description: "Battle the undead in this theatrical installment of "Zombies". New twists and clues could uncover the final plan. It's show time!"
2. "Five" - The Second Map is unlocked when you beat the campaign.( beat it on regular to get it).
Description: "The Pentagon is under attack! Washington is going to DEFCON 1 in this installment of "Zombies".
3. "Dead Ops Arcade" - Third Map. When your in the chair in the main menu stand up. You stand up by looking away from the TV and looking downward at your wrists. Next, pull back both left and right triggers until you stand up (Keep pushing and pulling the triggers). Walk towards the back of the room until you find a computer. It will pull up a command prompt and ask for a password which is "RUSALKA" then press enter. Next type in "CD" and press Enter. Finally type in "DOA" and press Enter. It will pull up an arcade looking game named "Dead Ops Arcade." Go in and Play and there you unlocked it.
Description: "Step back through time with this retro arcade zombie adventure and do battle with the forces of the Cosmic Silverback".
*The original four maps (Nacht der Untoten, Verruckt, Shi No Numa, and Der Riese) will return to CoD: BO. However, you must buy the hardened or prestige edition of the game for these maps to be unlocked.
A code should be packaged in the hardened or prestige edition of the game.
Just tested that password it dont work but
type cd then hit enter then type DOA hit enter that gets the arcade goin