为 索蓝蜘蛛 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！
Reach
When Thran Spider enters, you and target opponent each create a tapped Powerstone token.
: Look at the top four cards of your library. Put one of them into your hand and the rest on the bottom of your library in a random order.
