24 DAYS OF SURPRISES: Count down to the holidays or any other special occasion and receive 24 days of One Punch Man-themed collectibles by opening a door each day. COLLECTIBLE PRIZES: This 24-day advent calendar features high-quality collectible items -- buttons, sticky notes, coasters, mini booklets, pencils, and more -- that are designed to last so that you can show off your love for One Punch Man year-round.