Years after Infocom died and Activision was about to put out a graphical Zork game, this parser game was commissioned and then produced by two Infocom writers (Marc Blank of Zork and Mike Berlin of Infidel).
The game is almost pure nostalgia, and fairly short. It compares to Unnkulia One Half, which was similarly a small promo game riffing on older material.
In this game you find an undiscovered part of the Great Underground Empire and explore it. The game is very small, with one big square that has doors leading to three smaller areas, each with 3-5 rooms. There are little models of Zork items, Grue references, and the heads of the two implementers waxing nostalgic. There are references to the IF MUD (essentially an elaborate chat room that was once a multiplayer online parser game) and so on.
If you have nostalgia for infocom, this game could be lots of fun. If you have just barely learned about ibfocom, maybe not so much. The actual games themselves are more fun.