Zork: The Undiscovered Underground

Zork: The Undiscovered Underground (or ZUU for short) is an interactive fiction video game written by former Infocom Implementors Marc Blank and Michael Berlyn and implemented by G. Kevin Wilson using the Inform language. The game was released by Activision on August 28, 1997 for free to coincide with the release of Zork Grand Inquisitor. ZUU can be seen as having two goals: promotion of the commercial title Zork Grand Inquisitor, and an attempt to reconcile with die-hard Infocom fans who may have harbored resentment against Activision for their role in buying Infocom in 1985 and subsequent closure of the company in 1989.

Zork: The Undiscovered Underground, a prequel to Zork Grand Inquisitor, is set in the year 1066 GUE. The game is played from the viewpoint of your character who is a private in the Inquisition Guard, tasked with exploring a recently discovered area of the Great Underground Empire. The game merges classic "Zorkian" references such as grues and zorkmids with elements created for the newer game, such as the Grand Inquisitor.

The purpose of the game is to explore and emerge successfully from the Undiscovered Underground. The player begins only with a low-quality Lantern and plastic imitation sword, a parody of the starting items from Zorks I, II and III. Upon entering the Undiscovered Underground, the adventurer is trapped by a freak avalanche. The only way to escape is to release the mutant Rat Ants (an echo from Starcross) and to direct them to the avalanche, which they dispatch in a manner reminiscent of Aesop's Fables. The player must demask a Grue vendor, killing it with light, to gain the four candy bars and place the relevant objects in the Mud Forum on the appropriate corresponding floor symbols. This unleashes a mutant chase reminiscent of Planetfall where the adventurer stays one step ahead of the Rat Ants because of the shrewdly placed candy bars. However, the escape comes at the cost of unleashing a Rat Ant epidemic onto the empire and forces the adventurer to flee from the wrath of the Grand Inquisitor.

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