Families are invited the World’s Largest Indoor Trick-or-Treat at Mall of America. This morning MOA's Erin Sheppard gave us preview. The Anaphylaxis & Food Allergy Association (AFAA) is sponsoring the Allergy-Free Zone located in Macy's Court. Families and kids with or without allergies are invited to enjoy Mad Science demonstrations and non-food treats for all ages. Other trick-or-treating families can start out in the Best Buy Rotunda where little ghosts and goblins can show off their imaginative attire in the costume contest. Prizes will be awarded to the top three costumes based on creativity and originality. Other entertainment includes a magician and spooky animal show. After the festivities, trick-or-treaters can visit more than 200 retailers to gather some sweet treats. Treat bags will also be given away in Nordstrom Court.