14 Cards per Pack, 14 Packs per Box. Look for Exclusive Holo Foil Parallels. The 2026 Topps Series 1 Baseball Celebration Mega Box arrives just in time for MLB Opening Day, building on the flagship release and continuing the celebration of 75 Years of Topps Baseball. Celebration delivers the 350-card Series 1 base set, featuring today’s biggest stars, top rookies, Future Stars, League Leaders, and team cards. Collectors can look for 75th anniversary-themed inserts and parallels that honor the brand’s rich history and legacy in the Hobby. The Celebration Mega Box adds exclusive base card parallels and inserts. Returning favorites include Dugout Peeks, Walk this Way, and Gameday Drip, alongside trading cards highlighting team mascots. Autographs and relics remain a cornerstone of the experience, delivering the hits collectors expect from Topps Baseball.