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'You may exile a blue card with mana value X from your hand rather than pay this spell's mana cost.
Counter target spell if its mana value is X.
'Spells can't be countered.
Each instant and sorcery card in your graveyard has flashback. The flashback cost is equal to that card's mana cost.
'Avoidance — Whenever you cast a noncreature spell, exile up to one target nonland permanent you control, then return that card to the battlefield under its owner's control.
'As an additional cost to cast this spell, sacrifice a creature.
Search your library for a card, put that card into your hand, then shuffle.
'As an additional cost to cast this spell, pay X life.
All creatures get -X/-X until end of turn.
'When this creature enters, put target creature on top of its owner's library.
'If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead. If an effect would put one or more counters...
'Counter target creature or sorcery spell.
'Counter target spell or ability that targets a permanent you control. This spell costs {7} less to cast if it targets a spell or ability that targets a creature you...
'As an additional cost to cast this spell, sacrifice a creature.
Search your library for a card, put that card into your hand, then shuffle.
'Whenever a land an opponent controls enters, that player loses 2 life and you gain 2 life.
'As an additional cost to cast this spell, pay X life.
All creatures get -X/-X until end of turn.