Alright, folks, I need your help.
I read through a version of D&D when I was way younger and loved the lore entries for everything- the monsters particularly.
One monster's entry stuck out to me. It described a beast that slumbered in a cavern at the edge of the world, only to be awakened when someone on the material plane would speak it's name three times, whereupon it would cut a swath through the living world until brought down again. Subsequently, to speak the name was taboo in all societies.
Here's the catch. I don't remember which book the monster was in, what edition of D&D it was, or almost any other details. That little wisp of a memory is all that I've got.
I'd like to know what, exactly, that creature was, just so I can find it again with the other source material that I read at the time. I will likely remember the name when I read it, and TVtropes has failed me, so;
Any guesses?
That sounds like the original write-up for the tarrasque, from the AD&D Monster Manual II (1983). Let me check my notes...
EDITED TO ADD...
(Just came down from the attic with my old AD&D books.)
Here's the relevant text that I was thinking of...
It is fortunate that the tarrasque is active only for short periods of time. Typically, the monster comes forth to forage for a weekor two, ravaging all but a few square miles of 1and. The tarrasque then seek sa hidden lair underground and lies dormant, sleeping for 5-20 months before coming forth again.
The other thing that I thought your quote might be was the write-up of Hastur the Unspeakable from the unsanctioned Cthulhu Mythos section of the first printing of AD&D Deities & Demogods (1980) before Chaosium hit TSR with a cease-and-desist order...
Any time the hame "Hastur" is spoken, there is a 25% chance that Hastur will hear and send 1-4 Byakhee to slay the speaker. If the Byakhee are defeated, there is a 25% chance that Hastur himself will appear to destroy the blasphemer.
Bah. The Tarrasque fits most of the description the best, and I would have settled on it a while ago, if it didn't depend on that name awakening thing. I've never read of a Tarrasque that cared enough about mortals to depend on waking up when someone said it's name. And I know it wasn't an old god!
It's possible that I just mashed two entries together in my memory from that long ago, I guess- I could swear that it was one creature, though.
Thanks for digging the books up, Haladir.