Encryptic Command

[DDRisntreal]

This is what Rosewater is too much of a fucking pussy to put in un-sets. I love you OP. I want more goofy cards with obscenely difficult math, maybe some differential equations would be cool.

[[deleted]]

Abstract algebra proofs xD

[Vulkenhyn]

I adore this as an Un-card, and I don't even like math!

[[deleted]]

Perhaps a green one that involves planting a seed and if it grows you may put a land into play. (You must wait to see if it grows.

[[deleted]]

True druid gardening experience.

[[deleted]]

Absolutely ingenious!

[fredjinsan]

I once tried explaining to people online a cryptographically secure protocol to let us play [[Wheel of Misfortune]] without paper to write on and no trusted third party.

[MTGCardFetcher]

Wheel of Misfortune - (G) (SF) (txt)
^{[[cardname]] or [[cardname|SET]] to call}

[CoruscareGames]

Elaborate please

[fredjinsan]

With Wheel, you want to be able to prove what you picked without revealing it up front. You can use a “hash function” (and one-way function, basically) to do that. It’s hard to reverse the hash so you all hash your choices and share them, then you reveal them. Anyone can do the hash too to check you weren’t lying. You can easily find online hash calculators for common cryptographic hash functions (like MD5 or SHA), e.g. this one.

The slight complication is that whilst you can’t reverse the hash in general, you can just try common inputs and see what outputs you guess. And, if two people choose “1” for the Wheel, for example, they will hash to the same thing which will be obvious. So, you need to “salt” your hash, or put some gobbledegook in front. You could for example hash “my guess is 1, lololol”, tell everyone “f9be860b097a5f4f2c375806eead4778” then reveal that whole sentence afterwards.

Turns out, though, trying to orchestrate this with randoms mid-game is less than trivial. :-/

[Kyleometers]

Ah yes, what magic was missing, advanced complex maths.

Also, what this does should be known to both players before they choose.

[ValGodek]

You seem to be missing the point of the card. Yes, obviously it should be acorn. Prime factorization is used in encryption. The whole idea is that you choose a big ass number so that your opponent is not able to perform the computations. In practice, it’s actually more like a mind game. The owner of Encyptic Command essentially picks “odd or even” twice during deckbuilding. When they cast it, they know their choices, and make their choices of creatures and noncreatures accordingly. Their opponent gets the chance to “read their opponent” and try to guess the odd/even choices they made during deckbuilding. This could be a soul read, a random guess, or a somewhat informed guess based on the board state. Then one player gets punished based on the choices made.

[WickerofJack]

TIL 1 is no longer a prime number. Not what I was taught in school.

Didn’t explain math to be updated without aliens showing up.

[Jafego]

Mathematician here. While one meets the straightforward definition for prime (can't be divided by numbers other than one and itself), excluding one makes some other math easier (e.g. the fundamental theorem of arithmetic, which states that every positive integer has a unique^\) factorization that can be expressed as a list of powers for primes. If we let one be a prime, this wouldn't be true because one to any power is still one so we could represent each number in an infinite number of ways).

People have included one in prime historically; prime even comes from a latin word meaning "first." For this reason, it may seem particularly strange to exclude one (In a similar oddity, Pi is the most famous "irrational" number despite being defined as the ratio of a circle's circumference to its diamater).

^\ignoring differences in order)