Check out the first Merlin card to be revealed from The First Chapter Merlin, Self-Appointed Mentor

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There were even full-size mascot costumes of the Poncho Pikachus for Pokmon Center events
They also need absolutely no maintenance or improvement, so you can keep one of these in your bag for years and continue to have a consistently enjoyable experience
When crunching the numbers, it quickly became clear that Secret Lair Bonus Cards and Mystery Booster 2 came out on top