为 血脉救济 寻找最佳的先驱套牌，包括其胜率、热度，以及该牌在万智牌：竞技场中的合法赛制！
Target opponent loses 3 life and you gain 3 life.
Madness (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)
