The Magic Trilogy was meant to be a set of three games
using the Z-Vision engine following the resurrection of the Great
Underground Empire on to the war that divides Zork between the East and
West Lands. Zork the Grand Inquisitor was meant to be the first part of
the Magic Trilogy, the following paragraph is an extract from a press
release that Activision released when Zork Grand Inquisitor was in
development around 96 or 97.
"In Zork Trilogy II, the player assumes control of the
Underground and must protect it from hordes of treasure hungry adventures,
while also quelling a Granola Rebellion. Following in Zork Trilogy III,
the Brog and the player lead the battle between the Eastlands (the good
guys) and the Westlands (the bad guys) in the epic conclusion that spans
the entire Zork universe."
After the sales figures came in from Zork Grand
Inquisitor Activision decided that it was not financially viable to finish
the Magic Trilogy, so the finally of Zork has been left open and
unfinished.