When it comes to costumes, Katy Perry never disappoints, and her new Halloween-themed advertisement for PopChips is no exception. We love her Elvira-inspired look, from the vampire fangs to the sexy LBD. In honor of Halloween, we're giving away the actual sheer mesh Brian Lichtenberg dress Perry wore in this photo. Click below to enter for a chance to win. You can enter once a day through October 31st, so good luck!