zork is a game mode in black ops. you unlock it by going to thecomputer behind you after the start menu.
On the computer terminal type in zork and you will receive a trophy.
While sitting in the chair at the main menu, begin hitting both triggers rapidly. You will be able to stand up and walk around the room. Walk behind the chair and access the terminal. Type in "Zork"....
get out of the chair by pressing L2 and R2 for ps3 or LT and RT for xbox and go to the computer and type in zork
First you have to get out of the chair then walk around until you find the computer then enter zork