R74 is my personal favorite. Deep blue and for the most part, black wont glow reddish under it. However, I have been known to branch out from that, so I would say if Horror is your game, Red, Green or Orangeish should probably be where you are looking. I personally think Orange might be too happy, would avoid. Purple to me is a
bit more elegant, really more a Hamlet dies than Freddy kills sort of color, no?
I think personally, for a horror show, I would do some sort of blue-green downs with breakups in them focused soft, and do a ligher
overlay with like 90º units with a Full
CTB in there (I like AP2000 because it was available to me) and a harsh shatter or something in there, focused hard and run at 30-45%, so it will give texture to the show, and if you focus it so that its pointing more US or DS than straight down, it can make some excellent shape effects.