Title: Message
Fair usage includes reference to cultural icons. Cthulhu is a geek cultural 
reference.
Thanks
Fred Poutre
Cloven Fruit Games
 
  I 
  always understood that there was a certain amount of Public 
  Domain with Cthulhu. Lovecraft himself enthusiastically endorsed other 
  writers to expand upon the mythos and write within his world. Only certain 
  phrases and creations have been copyrighted by Chaosium, and for the most part 
  the whole issue of copyright was cocked up as he never stated in his will who 
  should control his work. Indeed, work earlier than, I believe, 1923 is Public 
  Domain (last I checked).
   
  Also, aside from Chaosium's Call of Cthulhu (a scenario for which I'm 
  currently in the middle of working on even as I take time out to write, here) 
  and related card game, let's not forget other Cthulhu-inspired games such as 
  Cthulhu 500, Munchkin Cthulhu, Arkham Horror, Do You Worship Cthulhu?, 
  etc. I've even seen Cthulhu referenced quite blatantly in cartoons 
  without, I'm sure, any fear of reprisal. Such as in The Grim Adventures of 
  Billy & Mandy in which there was an episode entitled "The Prank Call 
  of Cthulhu".
   
  So I 
  don't actually think there would be a particular problem for the most part on 
  the copyright front (so long as the terms or phrases that *have* been 
  copyrighted are avoided or, at the least, paraphrased). Enough of the key 
  ingredients that make up the mythos are free to make use of without any real 
  problems. Despite that, alas, I agree that Cthulhu Fluxx may well be a 
  pipe dream.