禁制

キッカー{2} （あなたはこの呪文を唱えるに際し、追加で{2}を支払ってもよい。）
呪文１つを対象とする。それの点数で見たマナ・コストが２以下なら、それを打ち消す。禁制がキッカーされていたなら、代わりに、それの点数で見たマナ・コストが４以下なら、それを打ち消す。

Prohibit

Kicker {2} (You may pay an additional {2} as you cast this spell.)
Counter target spell if its mana value is 2 or less. If this spell was kicked, counter that spell if its mana value is 4 or less instead.

Modern Horizons

Kicker {2} (You may pay an additional {2} as you cast this spell.)
Counter target spell if its converted mana cost is 2 or less. If this spell was kicked, counter that spell if its converted mana cost is 4 or less instead.

Duel Decks: Jace vs. Vraska

Kicker {2} (You may pay an additional {2} as you cast this spell.)
Counter target spell if its converted mana cost is 2 or less. If Prohibit was kicked, counter that spell if its converted mana cost is 4 or less instead.

Invasion

Kicker o2 (You may pay an additional o2 as you play this spell.)
Counter target spell if its converted mana cost is 2 or less. If you paid the kicker cost, counter that spell if its converted mana cost is 4 or less instead.

If a card or token enters as a copy of a permanent, the new permanent isn't kicked, even if the original was.

If a spell's kicker cost was paid, the spell is "kicked."

If you copy a kicked spell on the stack, the copy is also kicked. If the copied spell is a permanent spell, the token the copy of that spell becomes when it enters is also kicked.

If you put a permanent with a kicker ability onto the battlefield without casting it, you can't kick it.

The kicker ability doesn't let you pay a kicker cost more than once.

To determine a spell's total cost, start with the mana cost (or an alternative cost if another card's effect allows you to pay one instead), add any cost increases (such as kicker), then apply any cost reductions. The spell's mana value remains unchanged, no matter what the total cost to cast it was.