为 White Widow, Free Agent 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！
When White Widow enters, choose one −
* Put a +1/+1 counter on each of up to two target creatures.
* Return target artifact or enchantment card from your graveyard to your hand.
