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This list contains a smattering of the best discard cards across Magic formats
Bruenor Battlehammer , appropriately enough, is a fighty boy, at 5/3 for a mana cost of four, gives creatures you control +2/+0 for each equipment they have on them, and allows you to equip one Equipment card for free each turn
Great Hall of the Biblioplex Great Hall of the Biblioplex works great in control decks because it gives them a threat in the mana base, so they dont need to skimp on interaction when adding a win condition
13 cards of rarity Rare or higher per pack
The fact that she flips into a Planeswalker just by drawing three cards, which, by the way, her Clue helps you do, makes her an absolutely fantastic card in competitive formats