Elvira's Friday the 13th
From Disney's Hollywood Studios Wiki
Elvira's Friday the 13th was a special event that happened Friday the 13th in 1995-1997. Special events included Disney villain character Meet and Greets, a special edition of "Sorcery in the Sky" fireworks, extended park hours, especially for the Tower of Terror, and a motorcade featuring fifty Harley Davidsons motorcycle motorcade up Hollywood Boulevard, all hosted byt the Mistress of the Dark herself, Elvira.
This event was eliminated most likely because of the sporadic timing of Friday the 13th from year to year. For example, in 1996, it was celebrated in September, with the Halloween Season not to far away, but in 1997 it was celebrated in June, in the heat of the summer.