Call of Duty: Black Ops features a few Easter eggs to uncover including the old DOS adventure game, Zork I.
Gamers who love to hunt down Easter eggs in their favorite titles may get a kick out of Call of Duty: Black Ops. According to recent reports, there are at least two, both of which can be accessed from the game's main menu.
As seen in the video below, players are strapped down to a chair mounted in front of the main menu. On the Xbox 360 version, they can escape by tapping LT and RT repeatedly (use the Spacebar on the PC) until the arms break free of the straps. Once unsecured, players can actually roam around the area and eventually come across a PC running the old-school classic DOS.
Here's where the Easter egg fun begins. Type in "DOA" and the old computer will load up a top-down zombie shooter called Dead Ops Arcade-- this unlocks the "Insert Coin" Xbox 360 achievement. Type in "ZORK," and the PC will load up Infocom's classic adventure game Zork I: The Great Underground Empire in its entirety--this will unlock the "Eaten By A Grue" achievement.
For the uninitiated, Zork I was one of the first interactive fiction computer games, published in 1980 and the first part of a trilogy. The game originally appeared on the TRS-80, Apple II, the Commodore 64, the IBM PC and a few others, and was installed using the amusingly oversized 5.25-inch and 8-inch floppy disks.
Activision purchased Infocom back in 1986, and has since dissolved the studio. Activision still owns the licensing rights to the Zork franchise, allowing the publisher to include Zork in any Activision release. That could also mean Activision may have slipped in other classic titles.
UPDATE: Players can actually browse through the virtual PC, typing "DIR" to see its full contents and "HELP" to see a list of commands. There's a good possibility that Activision has hidden other Easter eggs on the PC, so gamers are encouraged to experiment.
Additionally, an Eminem song can be activated on the second zombie map called "Five." Simply find and activate the three red telephones.