インスタント
助力(他のプレイヤー1人が、この呪文のコストを最大
支払うことができる。)
呪文1つを対象とし、それを打ち消す。
You may reveal a card with assist and discuss how to pay for it before you begin to cast the spell. Targets are chosen for that spell before you choose another player to help you pay for it and before that player has committed any mana to doing so.