"NEEDS YOU," intoned the door abruptly, in a precise, hollow voice: "NEEDS YOU, BAA, BAA, BAA. OURUBUNDOS — "
The gathered Northmen dropped their spades. Many of them made religious signs with their fingers. Eyes round, they clutched their weapons, breathing through their open mouths.
"DOG MOON, DOG YEARS," moaned the door: "BAA, BAA, BAA."
And to each ritualistic syllable, Tomb made a suitable reply. Their dialogue lasted for some minutes before silence descended and he began again the process of moving his hands across the ancient script.
"GOLEBOG!" screamed the door.
A brief, intense flare of white light obscured the Dwarf. He staggered out of it, beating at his clothes. He chuckled. His hair reeked, his leggings smouldered. He blew on his fingers. "The door mechanism has become insane over the years," he said. "It — " Here, he said a word that no one knew " — me, but I misled it. Look."
...As Cromis entered the bunker, the door whispered malevolently to him, but it left him alone...
- M. John Harrison, The Pastel City.
Sentient doors in ancient dungeons often go mad, having long ago forgotten their original purpose, or failed to perform it for so long that they have become confused. Each time a group of PCs comes across a sentient door, randomly generate how it reacts by rolling a d12 and consulting the following table:
1. The door whispers vague threats about what lies ahead. This has a 10% chance of being accurate.
2. The door hisses "I'm behind you" after being passed through.
3. The door shuts itself 10 seconds after being opened, regardless of who or what is standing in its way. It causes d4 damage.
4. The door shouts incoherent gibberish if disturbed (i.e. touched).
5. The door announces that it is offended by the presence of intruders, and has to be begged and cajoled to open.
6. The door makes a very human weeping sound as the PCs approach, and begs them not to open it. There are no consequences if they do so.
7. The door is apparently friendly and offers information about who has opened it recently. 10% of the time the information given is accurate.
8. As above, but there is a 90% chance of the information being accurate. However, the door will also tell the next set of passers-by about the PCs.
9. The door makes a loud, horrible wailing sound when opened, and doesn't shut up.
10. The door can be opened, but the next time the PCs come this way, it will refuse to do so.
11. The door sucks magical energy. There is a 50% chance that each passing magic-user will forget a randomly-determined spell.
12. The door offers in a loud voice to answer three questions about the dungeon. Its answers are absolutely truthful about the state of play as the door understands it, i.e. 3000 years ago.