Originally Posted by Madscientist
I am not an expert for DnD lore.

Are the great old ones the same as the Qlippoth, creatures that lived in the abbys before the demons ruled it?
This is a link from pathfinder rules, but the stuff about monsters seems to be the same as DnD, only the gods are different.

I fought Demogorgon in BG2. It was a demon lord, and when it is a demon it cannot be a great old one, I guess.

Well in 4th edition it is said that Demogorgon is a primordial but do to the abyss he turned into a demon so he is both a demon and a primordial

Cthulhu: FOR THOUSANDS OF YEARS I LAY DORMANT, WHO HAS DISTURBED MY- Oh its you...
Warlock: Greetings my lord-
Cthulhu: LET ME SLEEP-