Building 10 rooms

FALSE CACTUS:      PLANT
CAVE ELEMENTAL: MONSTER
CIRCULAR SCORPION: VERMIN
MOON ORC: HUMANOID
SAND GIANT: BOSS
SUN FOWL: CRITTER

I
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D
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J--C--E
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B--G
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H--A
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F
Room A.
SMELL: Dry and musty, like mummy wrappings and black mold.
Dungeon cenote. Sides overgrown with FALSE CACTUS, climbdownable. Beautiful turquoise blue water. Bioluminescent bacteria intelligent, psychic, capable of projecting terrifyingly potent hallucinations/activating devotional centre of brain to make you think you see God. Bottom of cenote littered w/ human skeletons from sacrifices. Bacteria feed off flesh. One exit through underwater tunnel, skeleton in tunnel clutches bag of diamond dust and wears water-damaged RING OF THE JUNGLE. MOON ORC cultists soon to return.
Room B.
Room shaped like inside of tetrahedron. Anyone standing in etched circle in room's centre teleported to random other room of dungeon. Can be controlled by fetching tetrahedronal crystal in room A, will grant access to secret treasure chamber w/ no doors leading to it. Someone has to stay behind to teleport you out again.
Room C.
MOON ORC marketplace. Stalls selling rusted-through pots, moldy fruit, actual piles of shit. Violence prohibited in marketplace, they will not hurt you as long as you stay within the prescribed boundaries and don't break any of their weird taboos.
Room D.
SIGHT: Walls made of petrified wood, as if you're in the bole of a huge ancient tree.
Long flight of marble stairs painted black and white like piano keys. Stepping on wrong stairs flattens them into slide, makes climbing extremely difficult, getting down fun. Somebody in room A knows secret pattern or it's hidden in mosaic on walls. Anyone who's a musician gets a bonus to working it out. You decide which side PCs start on.
Room E.
Actual dungeon, exists to hold prisoners. Guarded by pair of MOON ORCs, one sleepy, one watchful. They are siblings. Couple of human captives in pitiful condition, starving in cells. One is WAXOXIS the LYING MONK.
Room F.
Map room. Globes, nautical charts, atlases, blueprints, guidebooks. SAND GIANT studying X-marked plan of faraway island, so enthralled that it has difficulty noticing PCs. Exquisite rug on room's floor seems like abstract pattern, careful study reveals it to be map of dungeon itself.
Room G.
Bunch of MOON ORCs who were just pointlessly fucking sitting there waiting for something to walk in so they could attack it.
Room H.
SOUND: Slow, monotonous weeping. Sounds like it's been going for a very long time.
Bedchamber of three, four MOON ORCs. Sodden and filthy. Careful inspection of damp rags that serve as bedding will reveal a(n) GHOST FIGURINE in surprisingly good condition, but forces save against filth fever.
Room I.
Formerly a wizard's study. Now a breeding pair of SUN FOWLs has made a nest of the spellbooks, which reveal interesting magical snippets if closely examined. Torn-up pages, gummed back together, may have produced odd new spells.
Room J.
Observatory. Star charts, half-ground lenses, celestial globes, tables of astronomical data (looks like random numbers) and pulsar emissions. SAND GIANT mesmerized by whatever it sees through single enormous telescope. If you broke the telescope's lens you could climb out of the dungeon through it.