Okay a lot of people probably thought what? When they read the title so let me explain I'd like to see a incarnation of the Green Goblin that's not a multiple personality but an actual physical being. Instead being a product of Norman Osborn's psychie he could be like a psycho experiment of Osborn's Company gone horribly wrong and kept under wraps. I thought about this after rewatching his debut episode in Spiderman The Animated Series and seeing him in Spectacular Spiderman. They some times always make you wonder who the Green Goblin is Harry or Norman but what if he wasn't either of them.
Now you are probably wondering how could that work? Well the Green Goblin being introduced as an experiment gone wrong might be a good story line he could view himself as the true son of Norman(I think an incarnation of Green Goblin actually states he's the true son or something to that effect) and try going after Harry as a messed up way of proving himself. That or he could like always be psycho protective of Norman Osborn and go to such extremes that he frightens Norman and sort of becomes a dark reflection of Norman's sins manifested as living being. He could even go after Norman calling him weak and declaring himself the rightful heir.
But to be really honest the idea of Green Goblin, Norman, and Harry all being able to interact at once seems very appealing to me. What do you think?