Building 10 rooms

BONE CACTUS:     PLANT
CLOUD MANTICORE: MONSTER
PSEUDO-SCORPION: VERMIN
WOODEN IMP: HUMANOID
WOODEN MINOTAUR: BOSS
MERCURY IBIS: CRITTER

C--E
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H--G--A F
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D--B J
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I
Room A.
One passage being slowly walled off by WOODEN IMPs under supervision of cranky, half-asleep WOODEN MINOTAUR who is enforcing compliance w/ threat of physical violence, eternal torment.
Room B.
SOUND: Boom of distant explosions, clatter of drills.
Enormous pile of DECK OF FRIENDSHIPs, all exactly alike, dumped haphazardly in corner. Only one is real. The rest are clever fakes that have a 25% chance of working once and then break. Somewhere in room H is concealed the secret of finding the real one. Possibly in someone's brain.
Room C.
SIGHT: Walls are sandstone, gritty when you touch them.
Spiral staircase. Young WOODEN IMPs sliding down bannisters. Will run away if they spot you, bring back angry parents.
Room D.
Crossroads, but one exit just loops back around into the other one. Walls of loop contain shelves for entombed corpses w/ gold coins on their eyes and PSEUDO-SCORPION concealed in their flesh.
Room E.
SOUND: Coins clinking.
Staircase wraps around inner wall of well. One exit high up, one at water level. Water pitch black. CLOUD MANTICORE that lives in well usually not hungry, can be roused to surface by ringing bell at very top of shaft.
Room F.
Vertical shaft w/ rope hanging from ceiling, goes two-thirds of way to floor.
Room G.
Extremely steep slope. Rope required to go up, down. Your choice whether the PCs start at bottom or top. Outcropping of BONE CACTUS halfway up seems like it would provide handhold, does, but also tries to eat PCs.
Room H.
SIGHT: Flowers bloom everywhere, even where they shouldn't. Especially where they shouldn't.
Enormous mirror is scrying-portal to alternate realms. WOODEN MINOTAUR getting stern lecture from overboss in Plane of Chaos/other, better dungeon/Hell, will shortly emerge in extremely foul mood. If there is a mirror anywhere else in the dungeon this mirror will let you look out of it.
Room I.
MOTHASIUS the POLITE SHEPHERD and HOBBLANTA the CRUEL GARDENER fighting for possession of a PAINTBRUSH OF THE SEA, each with an extremely good argument for why it is rightfully theirs. Actually they stole it from the hoard of a WOODEN MINOTAUR, who had it as a birthday present from their underworld pen pal and to whom it is of great sentimental value.
Room J.
CLOUD MANTICORE den. Sulphuric fumes vent from somewhere deep within. Contains skeleton holding DWARVEN TRIDENT, which in addition to other powers gets +2 against CLOUD MANTICORE. 50% chance that CLOUD MANTICORE is out. Secret way out of dungeon, big enough for monster to fit through.