It's been a long time since this rumour came up for air but MovieHole are today giving us all an update on the possibility of a 'Freddy vs. Jason vs. Pinhead' movie!
The 'Freddy vs. Jason' scripters Marcus Swift and Damian Shannon (currently working on the upcoming 'Friday the 13th' remake script) have previously mentioned that Pinhead himself was to originally appear at the end of the movie to possibly self-promote a future battle between the three horror icons.
"Yeah, the Pinhead ending was where - they [Freddy Krueger and Jason Voorhees] both get pulled down to hell at the end and they are still trying to battle”, Shannon tells Bloody Disgusting. “Pinhead comes out and separates them with chains and it's sort of a 'gentlemen, what seems to be the problem' moment."
"To make a movie based on that ending, where Freddy and Jason are in hell with HELLRAISER? That is practically impossible. You can’t stay in hell, you need victims, somebody to relate to. It would be too fantastical, I think."
So I guess that put's that to bed.