You say, Hallister the Mad Wizard, the creator of Undermountain already holds the title - well, perhaps for super dungeons. This dungeon is much smaller (at 1 inch = 5 feet scale) the total dungeon is 72 x 72 inches, however, that is sliced into 9 24 x 24 squares, each with it's own set door chambers, halls and doors.
The Mad, Mad, Mad Wizard's Labyrinth is a dungeon in 9 squares that form the full dungeon square. Posted below are the first two 24 x 24 sections, with one more coming that will go to the right of these two, then six more below them. Rules are once the entire party enters a square they can move about the rooms and doors they have access. Once the entire party (or confirmed party split with GM), enters another square, the previous square rotates 90 degrees clockwise, so attempting to reenter the door will take you to a different room. If you exit any of the outer doors, these link to the opposite doors in the square on the opposite side of the entire dungeon (2 squares away). While this could be used for any plot... here's one.
The Mad, Mad, Mad Wizard just died. He made deals with devils, demons, daemons, angels, aberrant beings, in addition to have been an epic level wizard. While multiple extra-planar beings are attempting to seize his soul for their agendas, the PC's sponsor also dealt with the wizard, and is owed his spellbook as payment. The PCs are told "You'll find his spellbook and a key on the desk, that you'll need to get out, in his study. Oh, and if you can't access the room, you'll need to go around to get there."
The party enters from the top left door. Notably, the study they find is in shambles and appears to have been hit by a fireball or some other fiery spell effect, but no book nor key. However, on a Perception check, the mirror on the opposite wall shows your reflection, but the room behind is elaborately decorated, with a desk shown with key and spellbook on it, in the mirror. The party cannot pass through the mirror - they'll need to go "around" to get there...
GP
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