This is my first Five Minute Friday Map, inspired by this meme on Google+.
It is a cross section of a spherical mini-dungeon. The PCs start in the center, teleporting or gating or dimensional shifting or somesuch to arrive there in the first place. There is a large window that looks out over a gap to a much larger window opening into a lush garden chamber lit from above. The light that comes out the window of the garden room is the only illumination inside the structure, providing indirect lighting all around the central opening. The only door out of the start room opens onto a log bridge over a gap. A demon beast of some variety is lurking below out of sight. Roll 1d6 1: Giant Demon Porcupine 2: Two Headed Demon Wolf with Human Hands 3: Demon Bear 4: Giant Demon Spider 5: Giant Demon Toad with Toothed Tongue 6: Demon Minotaur with Battle Axe from Hell
The light source is a miniature sun that hangs in the air in the middle of the room above the Garden Room. It does not produce heat but inflicts 2d6 damage per round to anything inserted into it, melting metal in 2d6 rounds.
All of the plants, bushes and trees in the Garden are contained in large ceramic pots glazed with magical symbols. They are a rare mixture of medicinal and poisonous herbs, trees bearing magical fruit and bushes with shadow berries useful for summoning dark creatures. Both the pots and the plants radiate magic.
Defeating the Demon Beast causes a portal to open up in the Start chamber that leads back to wherever the PCs came from. This portal will remain open for 2d20+4 rounds. It will begin flickering with blue light when 5 rounds remain.
The chambers directly above the start chamber are a wizard's comfortably furnished living room appointed with indestructible lounge couches and low tables (lower chamber with two doors and a ladder to a trapdoor above)
and a wizard's mostly looted and totally ransacked laboratory/library with a secret door to the wizard's back door, a teleportation chamber.
The secret chamber below the demon beast contains the magical machinery that generates the light source, controls the humidity of the garden chamber and links with the magical pots to keep the plants in perfect health, and summons a new beast automatically 1d4 days after the death of the last