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For three-mana, Rhystic Study either draws you a card off of each spell your opponents cast or it serves as one-sided Sphere of Resistance, both of which are absurdly strong effects
You have to do the math here to figure out what cards make sense
the hard part is the right variant (reverse holo, 1st Edition, Master Ball pattern)
A mana base can be simple (say, seventeen Plains in an all-white, 40-card deck) or it can be quite complex: featuring multiple colors of mana, lands with unusual abilities, and indirect methods of making mana (via artifacts, creatures, or spells)
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