Where in the books is this mentioned? —The preceding unsigned comment was added by Harry Potter Fantic 1 (talkcontribs).

Please sign your comments with four ~~~~. As for the question, it's in Order of the Phoenix. - Cavalier One(Wizarding Wireless Network) 00:57, 9 December 2007 (UTC)

I don't know what book you have or what country or state you're in, but in the paperback US edition, pg. 737 and 739, it says:

  1. Pg. 737: "Luna and I can stand at either end of the corridor," said Ginny promptly, "and warn people not to go down there because someone's let off a load of Garrotting Gas." Hermione looked surprised at the readiness with which Ginny had come up with this lie. Ginny shrugged and said, "Fred and George were planning to do it before they left."
  2. Pg. 739: "That's because it's colorless," said Ginny in a convincingly exasperated voice, "but if you want to walk through it, carry on, then we'll have your body as proof for the next idiot who didn't believe us..." —The preceding unsigned comment was added by 1290142 (talkcontribs).
This is most likely a potion not a spell, I don't think theres enough evidence to say its a spell. Perhaps we could modify this article? The Unbeholden 06:16, 7 November 2008 (UTC)
I agree that it's most likely a potion, based on the language used in describing it. The HP Lexicon also categorizes it as a Potion. Oread (talk) 17:02, 13 April 2009 (UTC)
Why do we have to categorize it as either a spell or a potion? Couldn't it be a naturally-ocurring substance? --  Seth Cooper  owl post! 23:58, March 28, 2010 (UTC)
Bumping. --  Seth Cooper  owl post! 20:19, June 3, 2010 (UTC)