We're playing 3.5e Savage Tide with 5e characters... and the DM uses the 3.5e stats for monsters because we are too strong 
  You have to get creative when you need to hit AC 35... or when there is a save or die 
	
	
		
			
	
Anyway, we do not relish fighting 3.5e Demogorgon, but if there is one artifact we would love: something that gives the party the equivalent of Mind Blank, as there is his aura of insanity and other mind-affecting crap with 3.5e save DCs that would seriously gimp the fighters in the group.
Anyhoo, here are his 3.5e stats, good luck
: Demogorgon (3.5e Monster) - Dungeons and Dragons Wiki
				
			like Aren Dagrost's gaze
		Anyway, we do not relish fighting 3.5e Demogorgon, but if there is one artifact we would love: something that gives the party the equivalent of Mind Blank, as there is his aura of insanity and other mind-affecting crap with 3.5e save DCs that would seriously gimp the fighters in the group.
Anyhoo, here are his 3.5e stats, good luck