昨天OC碰到的问题，对手第一张封锁舰被弃掉，然后我备战阶段横减费地，对手又打出第二张封锁舰，统御阶段不让我米拉西斯补牌。
再将问题简单化:我先行，备战阶段已经横过地（各种减费地），对手再打出河道封锁舰，能取消我下一个地区牌触发的效果能力？
答案是不能！
“每回合第一次”是绝对的，而不是从这张卡牌观点上看！
摘取国外论坛的相关例子：
local player group had a fierce discussion about a situation about this card. Lets say per example my opponent is first player and i have a river blockade in play he tries lowering marshalling cost by kneeling a fiefdoms the effect is cancelled by the active river blockade, he marshalls the iron throne (lannister card) some cards doesnt matter. Now its my turn i marshall into play a second river blockade i kneel a character of mine to do something so nasty its unheard of so he triest o cancel it with the iron throne, now does the second river blockade (just played) cancel the iron throne ? 3 of us said it did cause after playing the second river blockade the painted table is the first location triggered for that specific river
number of river blockade you have in play doesn't matter, only the first location effect triggered by your opponent this round is cancelled. this round it was his fiefdoms which was cancelled, so his iron throne works
the text of this card speak in absolute terms, also the first location knelt this round. This kind of ability are influenced by what happened during the round. The same applies for example to "disgruntled mercenary": if you manage to put him into play after the first challenge, it remains. That's because the text "of the round" always relate to absolute and not from the point of view of the card
英语水平有限，就不献丑翻译了，大伙凑活看吧。结论用红色标注了。
两个衍生的例子是：
