Harmonix has a new Rock Band game out on Tuesday called Rivals, and, well, let’s just say their new promotional ad is pretty dirty. Filthy, even. But that’s what you get when you round up Boston musicians and edit them together talking about poop, diarrhea, and other smelly-ass things that go squish in the night. In the video below — a playful attempt at explaining the game’s ESRB rating — a bunch of familiar faces from the Boston music scene come together and discuss various types of feces. We spy members of Party Bois, Ruby Rose Fox, Petty Morals, Razors In The Night, The Devil’s Twins, Acaro, and others, all taking part in the game’s new Rockudrama feature. “We reached into the bowels of our video footage to pull this together,” says Harmonix. We’re sure they did.