A set of ideas/concepts given to the author of any fantasy book, all of which must be used in the book. They include
- The mysterious wizard (often old and bearded)
- The broken weapon
- The powerful but apparently insignificant artifact (ring, stone, whatever)
- A major character must die (or appear to, but re-appear later)
Most of these appear in
LordOfTheRings, but they were at least reasonably original there.
I think this was invented by DaveLangford?, a SF critic and author. I first read it in White Dwarf, a UK gaming magazine, probably in 1980 or so