I'm not one to be super-picky on this. A player may concede at any time and I'm not going to force a player who has conceded a game to show those cards to their opponent. But perhaps other judges will disagree with me.

104.3a A player can concede the game at any time. A player who concedes leaves the game immediately. He or she loses the game.

When the player leaves the game, they take all owned cards with them. Since the player's deck is no long in a public zone, it is no longer public knowledge. At least, that's how I would rule it.

I am generally of the opinion that if a player /looks at/ the cards, they're obligated to /reveal/ them. Counterbalance is a common example - you don't get to look at the card, you only reveal it. If you look at it and decide you don't want to reveal your secret sideboard tech just yet, too bad - that information is now public. You've either looked at extra cards, or resolved counterbalance incorrectly.

In other words, if you don't want to reveal them, don't reveal them. You can't get the shot at a blind flip for Counterbalance /and/ the ability to hide the next card. Same with “play with the top card of your library revealed” effects.

Now, Mindslaver/“can I see your sideboard” is a common exception to that, but I am of the mind that a player may not hide free information about the game state from their opponents.

With the situation given here, there's no advantage gained by NAP by allowing the mill to resolve (he was milling his entire library, there's no information he improperly gained). So while I maintain that NAP is not permitted to flip his library and then hide the cards, I don't care strongly about it, and would neither infract nor require NAP to reveal his entire deck now (between games).

Edited Dan Collins (June 13, 2016 10:18:52 PM)

Originally posted by Frankie Hughes:

104.3a A player can concede the game at any time. A player who concedes leaves the game immediately. He or she loses the game.

As a reference, this goes as far as conceding during resolution of a spell or ability, i.e.:

AP casts Slaughter Games.
NAP: “Resolves. What do you name?”
AP names a card.
NAP concedes, and scoops, without revealing anything.

Edited Francesco Scialpi (June 14, 2016 04:18:51 AM)

Originally posted by Scott Marshall:

I could pick up the top card of my library, intending to reveal it for Dark Confidant; realize that you haven't seen this card yet, and it's CMC is enough to kill me; concede before revealing it. I could do the same for Counterbalance, or Courser of Kruphix. (Yes, this is contrary to what Dan said, above.)

And why do we allow this? Why not tell the player that the rules say to reveal the card so if he can see it the opponent can see it as well?

Why be so mean? :p

(Yes, I'm serious.)

d:^D

Is there any other case where we allow a player to take an illegal action on the basis that politely asking that they follow the rules would be “mean”?

Edited to add: Obviously this is a situation that doesn't come up all that often, so I don't want to spend much more time arguing it. My position is that I'm not interested in allowing this player to look at his library before deciding if he wants to mill himself, or reveal for Bob. There are two players in the game, and all the opponent is asking is that he be allowed to see cards that he is entitled to see.

In the case of a player rushing a Probe or Thoughtsieze, picking up their cards once their opponent draws, or chooses a card, but before they're finished writing them down, it is well established that we will ask the player to keep their hand revealed until the opponent has had a chance to write down the cards. I can't look at the top card of my library before deciding if I want to reveal it to Counterbalance, so either I've looked at a card for no reason, or I've intentionally hidden free information from my opponent.

Edited Dan Collins (June 15, 2016 11:11:28 PM)

What illegal action are we talking about? The “at any time” seems to be quite all-compassing.

Originally posted by Jona Bemindt:

What illegal action are we talking about? The “at any time” seems to be quite all-compassing.

So, full disclosure: this argument pops up every six months and has been beaten to death. But for everything “everyone” knows about, someone learns about it the first time on any given day. Congratulations, you're one of the ten thousand!

The argument generally goes as follows: no instruction allows the player to look at any cards. The active player could have conceded before the cards were revealed, in which case AP was not entitled to look at them; or, AP could concede after the card is revealed, in which AP is not entitled to conceal them.

The general consensus of program leadership, however, is that this technical reading is unnecessarily “mean,” to use Scott's words. Concession can happen at any time, even half-way through the process of revealing a card, when it's only revealed to one player. This isn't something we should worry about.

Beyond that, however, I'll remind everyone that this argument has been discussed over and over and new ground it unlikely to be broken. It's also a fairly extreme corner case; I've literally never seen this call nor heard of it happening live. I'm sure that it comes up from time to time, but it's so uncommon that the payoff to getting a “perfect” policy about it is not worth the effort.

Originally posted by Eli Meyer:

I've literally never seen this call nor heard of it happening live. I'm sure that it comes up from time to time

It came up (infrequently!) when Mindslaver was commonly played - but that doesn't contradict what you said, Eli. If anything, it confirms your “corner case” description.

Also, Eli, thanks for the summation, and especially for the xkcd link!

d:^D

I have a (somewhat) related question: if a player asked you if they could look at the top card of their library before deciding to either reveal for counterbalance or concede, would you let them?

“You can concede at any time.”

Thanks for the responses everyone.

It makes sense that they are not required to reveal the information, but I wanted to be sure. I apologize if this is a reposted question.