A kicker is an additional cost that appears on some spells. If you choose to “kick” a spell—that is, if you choose to pay its kicker cost as you’re casting it—the spell will get better in some way. You’ll pay the total cost all at once, and you can kick the spell just once. Note that paying a spell’s kicker doesn’t change the spell’s “mana cost” or “converted mana cost,” if some other effect looks for those.
What will happen if you kick a spell varies from card to card. A kicked instant or sorcery spell might do something in addition to its normal effect—or it might do something instead of its normal effect! A kicked creature or enchantment spell might enter the battlefield with counters on it, or it might have an ability that triggers when it enters the battlefield. Be sure to read each kicker card carefully to see what its bonus is!
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