The PCs have nowhere to go and no leads. The eerie skull’s voice, presumably the leader of the cult of Iuz, suggested he was somewhere in the dungeons of Castle Greyhawk. However, with the Tower of War cleared, the Tower of Zagig inaccessible due to an endless staircase, and the Tower of Magic warded by the powerful and insane Grandfather Magic, the PCs are at something of a dead end. They do not know the command words to overcome the staircase’s spell, and they do not have Zagig’s Key, the only item that would convince Grandfather Magic to remove his wards…
After several days of inactivity and frustration the PCs are approached in the Green Dragon Inn by Tirra, leader if the thieves’ guild in the Free City of Greyhawk. She does not hide her affiliation, leading the PCs to a safsehouse to explain her plan. Tirra tells the PCs that she knows where they can find Zagig’s Key, and she will tell them if they promise to recover a bronze monkey statue valued by a collector from the same location. When the PCs agree Tirra tells them the key is located in Zagig’s Study, a secret room in the Tower of Wizardry.
She goes on to explain that the PCs will enter a magical bottle that one of the guild members will smuggle into the tower. Once inside, the PCs will emerge and find a book in the library entitled, “the Yragerne Accord of 393,” which will reveal the means to enter Zagig’s Study and retrieve the items.
The next day the PCs enter the bottle and wait the instructed twelve hours before exiting. They find themselves in private quarters in the Tower of Wizardry. Donning purple robes provided by Tirra, they exit the room and begin their search. They immediately come upon a group of wizards surrounding a summoning circle, one of which is struggling to contain a summoned hezrou. The wizards pay the PCs no mind, who move into the vast library. Upon searching for the book they are ambushed by an invisible beholder. Before they are able to slay the aberration it kills Nyet with its finger of death eye ray. Blaiz stuffs Nyet’s body into Heward’s Handy Haversack. The PCs quickly find the Yragerne Accord of 393, telling them that by speaking the name of Zagyg in the Chamber of Seven Secrets will open the indigo pillar and grant them access to Zagig’s Study.
Upon reaching the chamber the PCs attempt to solve the riddle of the seven. Upon failing several shield guardians animate and attack. Deciding to waist no time the PCs speak Zagyg’s name and escape up a ladder that appears inside the now open indigo pillar.
The top of the ladder opens into a study of ancient texts and candlelight. The PCs find several books and scrolls of great value before moving past the first shelves to find the great Mordenkainen.
The great wizard questions the PCs only to see their trivial, nervous responses. He pulls Zagig’s Key from his desk drawer and tells the PCs the tale of Rary betrayal of the Circle of Eight. He tells them of the betrayal of Lord Robilar as well, but says that Robilar’s betrayal was unwarranted and made no sense. Mondenkainen says that Robilar must have touched the Orb of Opposition, forcing him to change places with an evil extradimensional doppelganger named Bilarro. Mordenkainen would have the PCs recover the Orb and force Bilarro to return to his home plane, freeing his old friend Robilar. With that the great wizard gives the PCs Zagig’s Key and wishes them luck.
The PCs return the bronze monkey to Tirra, who in returns gifts Rothgar Norebo’s Hand. She purchases the Yragerne Accord of 393 for 3000gp and wishes the PCs luck in their next venture into the ruins of Castle Greyhawk.