为 壮绝实验 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！
Exile the top X cards of your library. You may cast instant and sorcery spells with mana value X or less from among them without paying their mana costs. Then put all cards exiled this way that weren't cast into your graveyard.
