Er, can we assume our countably-finite libraries are equal in size? A combo that results in "Each player draws N cards" ... if there any way can it be used to deck an opponent? Or, imagine there was even a combo "Draw N cards and each opponent draws 2*N cards" - could THAT be assumed to be able to deck the opponent? Or does each player independently have as many cards as they might situationally prefer to have?

I have a question.

I found a deck that needs 4 cards to win. This means I will win on my 2nd turn going first and on my 1st turn going second.

Is this legal?

Perfectly legal. It's illegal if it can win before the blank opponent can take a full turn. But in that scenario, the blank opponent has completed one full turn before you win either way. You're golden.

Well then...

I guess I will participate.

that would probably be for the best

So then the number I gave along with my deck was for no reason? That's annoying...Oh well, it was a really low number compared to what most people would likely pick anyways.

most numbers are quite small

If each player could decide how big their library was in a situation that mattered, they would pick either the largest or the smallest number possible. I find it very hard to come up with a situation where the deck size matters and both players would not pick the same number. With "biggest number possible" being a number for argument's sake.

I could come up with situations where people would pick a very low number though, so maybe the situation is possible.

there is no biggest number possible, if there was such a number it could be made larger by adding 1

(also the best large numbers aren't even computable anyways)

It's an artificial construct. The idea of being "finite" implies there is some largest number possible, and we just don't know what it is. For the sake of a mirror match that would stall out, both players would pick "the largest number possible" and player 2 would get decked first.

No. The idea of "finite" means it can be defined. "Infinite," by contrast, cannot be defined.

So there is no "largest number possible" but instead a "largest number definable." But the problem, as Golgari already pointed out, is that once you define that number, you can add 1 to it to define a new "largest number definable" and repeat this process indefinitely. Or at least until we have somehow used every discernible sound and/or letter combination ("word") to define the numbers.

^ Don't give me that. You understood the main point, and this semanticism is just being facetious for the sake of it. For all practical intents and purposes if players want the biggest deck possible then they'll end up with the same deck size and whoever draws first in the stated situation will lose. Anything else is either pointless complication or deciding players can only lose to mill if the opponent has an infinite mill combo. If you want to make that a rule then just say so and stop picking at it just to be difficult.

For all real intents and purposes I'm just going to try to mill you to death as soon as possible.

A countably finite number is not a mathematical concept; a countably infinite one is. So the intent was probably a finite number. Which is how infinite combos are terminated in Magic: you must choose a finite number of repetitions for the loop.

Way I see it, if deck size only matters for infinite combos, we're good, we just assume that the combo runs enough times to mill the opponent; on the other hand, if somebody has a deck where the win is decided by who runs out of library first, we should each submit a finite number as our deck size. However, from the way the rules were worded, I got the feeling that deck size shouldn't matter, just that you can keep on drawing the designated card until the game is decided by some means other than milling.

P.S: it's Christmas, so I haven't found the time for scoring Progenitus yet. I'll see if I can do it tomorrow; if not, or if that's too late, please just use the symmetry tool.

Jim when you read this please look at my most recent message in your inbox. The one that isn't a deck submission.

I have a hard time convincing myself that I lose to Spy. He gains no life from Verdict, I get Proggy back anyway, and he can't stop me from playing Exploration on my turn one. If he does not discard me, I can get to Progenitus on three, or a bit later if he gives me a Beast. The best line I found for Spy on play is below.



Gotta go now, will look at this again later.

And I agree with Edacade on 5v7.

No (and this is not semantics). The idea of being finite is only needed if there is a thing that's not finite; and it is in fact used to define the first level of infinite numbers, by saying that it's a number that's bigger than any finite number. As Spy pointed out, there is always a larger finite number for any finite number. .

Again, if deck size matters, each of us should submit a number. This does not impact infinite combos, just decks full of Grizzly Bears where the guy who runs out of them the first loses the game.

my line was a turn off, turns out progenitus kills me when i'm on the play (i get zlehtnoba to 2 life by ignoring exploration)

i'll correct that score

Whoever proposed the format (Spy?) should think about this (I'll use a banned card for the example):

Consider the deck made of Forest, Glimpse of Nature, a lot of copies of Memnite. This can play all of its Memnites on turn one. If two such decks face each other, should this be a draw?

If yes, we should agree that everybody starts with the library of the same, very large, size (the number doesn't matter; say, a million?). If not, everyone should also submit a deck size.

As I understood the countably finite deck size proposal, that matchup should be a draw.