mtg cards that proliferate Rules Text: Proliferate, 98 then choose any number of permanents you control that had a counter put on them this way The 49 Best Proliferate Cards

While Appa notably only airbends your permanents, its possible airbending can be done to an opponents permanents

Whenever you cast a legendary spell from your hand, exile cards from the top of your library until you exile a legendary nonland card with lesser mana value

The need to attack with your creatures in order to receive a cost discount can be a bit awkward as it may force you to make some less-than-savory trades

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Then, the player can pay 5 to shuffle the deck and play cards off the top for free, which generates incredible value