At least two of the Silver Shamrock Masks from Halloween 3: Season of the witch are in the den among the collection of special effects.
Linda Blair once stated in an interview with Fangoria magazine that the original title of the film wasn't as exploitive, and as associate producer, she could have sued to fight the change, but it would have ended up costing her more money than she got out of the whole project.
Luana Patten was a child-turned-teen-actress, like Linda Blair (also like Donna Wilkes). The previous role was in 1970, where she played a young 30-year-old woman on Adam-12. Skip 18-years later, for this movie, she's not only older, but her character is billed as Old Lady.