Planeswalker Decks are the best way to sample what M21 has to offer," Magic: The Gathering Senior Game Designer Max McCall told CBR about the set. "They’re 60 cards, including four rare cards and one mythic rare planeswalker card. Each Planeswalker Deck uses the theme of its planeswalker... Each Planeswalker Deck has three other new cards beyond the planeswalker. The rares always lets you find your planeswalker. The commons and uncommons vary based on what each deck needs."