Allen has Sylvan Library in play, and reveals Terminus for his draw step. He chooses to stack his triggers so that Sylvan Library resolves first. After seeing all three cards, Allen realizes he doesn't want to cast Terminus. He also wants to minimize Nathan's knowledge about where Terminus ends up.

If I understand correctly, Nathan will always know if Terminus remains in Allen's hand, since it would have to stay revealed until the miracle trigger resolved.

If Allen puts back two cards including Terminus, will Nathan know whether Terminus is first or second on top of Allen's library?

Library is worded “For each of those cards, pay 4 life or put the card on top of your library.” A more direct question is if there's ever a time during that resolution where one card has been put back, but not the other.

1. Yes, Nathan will know if Terminus is put back on top of the library or not. Part of the miracle trigger is that the card is revealed from the time it's drawn until the miracle trigger resolves. If Allen puts it back, it stops being revealed, so Nathan will know that it's no longer in Allen's hand.

2. Assuming you're choosing to put back two cards, both cards are put back on top of the library at the same time, not one at a time. While your opponent will know that the miracle card is one of the two cards, they will not know whether it is the top card or second from the top.

Nathan Long
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