为 Brineborn Cutthroat 寻找最佳的标准套牌，包括其胜率、热度，以及该牌在万智牌：竞技场中的合法赛制！
Flash (You may cast this spell any time you could cast an instant.)
Whenever you cast a spell during an opponent's turn, put a +1/+1 counter on this creature.
