I totally cheated and am calling Clue (1985) a Halloween movie because of the big, spooky mansion. Really, I have no other excuse. I mean, there are murders a-plenty, but it's not exactly even a spoof on movies like House on Haunted Hill.
But it is a great cast, with one of the funniest humans to ever walk the earth, Ms. Madeline Kahn. She doesn't get a lot to do in this ensemble piece, and she's competing with Colleen Camp squeezed into a maid's uniform and Lesley Ann Warren given a bigger piece of the plot. Of course, the movie stars Tim Curry, Martin Mull, Christopher Lloyd, Michael McKean, Eileen Brennan and FEAR frontman Lee Ving.
Anyway, Clue is still Clue, and it still has one of my favorite Madeline Kahn moments.
So, you got that going for you.