Slasherthon I was every Friday the 13th.
Slasherthon II was every Halloween.
Slasherthon III was every Maniac Cop.
Slasherthon IV was a collection of slasher films we'd not seen yet. It was dubbed "Picking Up the Pieces".
Slasherthon V was every Nightmare on Elm Street
Almost all Slasherthons include a viewing of Halloween.