Saw this movie on HBO now.

It's a 2008 horror movie about a group of people who become trapped in a hospital and terrorized by ghosts. It has:

Bad acting
Hilariously bad dialogue
Decent production values
Takes itself extremely seriously

One look at the "ghosts" is honestly enough to qualify it for a rifftrax. They look like star trek extras. But beyond the cheesy effects it also tries to cram literally every horror trope in existence into one movie, it feels like it was made entirely by a focus group and then outsourced to China.

I had sign up here just to mention it because I think it's one of the most riff-able movies I have ever seen. I mean just the title alone is a gold mine.