Do you mean Radon?

( M3rx Winky winky bum bum poo poo titty titty!, Tue 24 Jul 2007, 14:54, archived)

I may mean that
:D

as it ends in *on

it's something green and nasty

oh oh.. I know "it's magical spirits"

*gets very sharp knives out*
( Discomeats I like pies!, Tue 24 Jul 2007, 14:57, archived)