-------------------------------------------------------------------------------- "if a red dragon fought a mind flayer sorcerer, who would win?" --------------------------------------------------------------------------------
If it is an ancient red dragon, my money's on her.
Would'nt even have to be ancient: red dragon's Will save is through the roof.
Don't forget the adult dragon is a 9th level sorcerer, too. DR10/magic is pretty good, with an SR of 23, Breath Weapon DC 28. It can use blind sight to counter the invisible flying flayer.