I’m thinking a giant puppet head a la the Poltergeist demon/clown heads or the giant creature from Midnight Snack 2 in Slaughter Sinema last year.
The way I picture it, they’ll have the big Stay Puft head scare, then one more Gozer scene with the Ghostbusters themselves as scares with the loud proton packs alongside maybe a dog or two to mix some things up, then a scene on the NYC street with the marshmallow smell and gunk everywhere with the Buster’s climbing out of the gunk as minor scares. Then one final room with the Ghostbuster’s celebrating in front of the apartment building with Slimer as a fun chase out scare.
I’ve heard a lot of people outside of this site saying that they hate the idea of GB as a house but I don’t think it’s that hard to come up with decent ideas for it. I think it has good potential to be at least as scary as ST was last year.