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{U}, {T}: Draw two cards. {R}, {T}, Discard a card: Mercurial Chemister deals damage to target creature equal to the discarded card's mana value.

Flying, haste You may cast sorcery spells as though they had flash. (You may cast them any time you could cast an instant.)

Counter target spell. You gain 5 life.

Exile the top X cards of your library. You may cast instant and sorcery spells with mana value X or less from among them without paying their mana ...