Why is my dungeon laid out like a d20?

[johnbragg]

So the rooms of this dungeon actually connect the way the faces on a d20 would connect, but from inside the rooms there's no sense of slope or vertical displacement as you move between rooms -- so that from outside the floors all might appear to face the inside of the "d20", but from the rooms the floor is always "down"?

In my idea, the rooms are all separate demiplanes connected by portals. The PCs should figure out pretty soon that it's not a standard 3D space--portals are often wider on one side than the other(1) the internal angles or dimensions of a room have no relation to the layout of the dungeon as a whole, etc. The standard d20 is the map, the way you can navigate the branching and reconnecting pathways. But there are a few steps of "clue" before the players should figure that out.

(1) The portal widths are keyed to the room numbers--the portal to the lowest numbered room is 6 feet wide, the median 8 feet wide, the highest is 10 feet wide.

The room numbers tell you room categories--primes are rooms with (semi) unique monsters, 4, 6, 8, 10, 12 either are polyhedron-shaped and therefore a challenge to get across from portal to portal, or just enormous cube shaped rooms with big honking polyhedrons sitting in them as clues. And the rest of the rooms are environmental encounters--the three portals are free floating islands in a pocket of the Elemental Plane of Air/Water/Fire, a room with an orb of Dispel Magic at the center that recharges every few rounds, a room of feywild with even more variable geometry than the dungeon as a whole, maybe an room of despair, etc.

But I like a lot of the ideas people have put out in the thread. I might swap out for some of those