wotc
If a card in your hand has {X} in its mana cost, X is considered to be 0.
If a card in your hand has {X} in its mana cost, X is considered to be 0.
If a spell has {X} in its mana cost, include the value chosen for that X when determining the mana value of that spell, even if it was cast for an alternative cost and no mana was spent on X.
Disrupting Shoal can target any spell, but does nothing unless that spell's mana value is X.
Magic: The Gathering · ™ & © Wizards of the Coast · Illus. Scott M. Fischer
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