Does “Going Infinite” necessarily end the game?
cirosantilli opened this issue · 0 comments
Magic the Gathering is Turing Complete
This leads to the following edge case, which I believe is not directly covered by any existing rules, although judges would in practice obviously just prevent this from happening / add it to the rules due to similarity with other rules and common sense.
We now have a 2 player legacy-legal way to build an arbitrary Turing machine in Magic in which neither player can take any actions once the machine starts executing:
which is an improvement to an older 4-player setup: https://www.toothycat.net/~hologram/Turing/HowItWorks.html
What this means, is that you could setup a board state where:
- players cannot take any actions
- determining whether the game draws (due to an infinite loop) or you win the game would be equivalent to determining the answer to a famous unsolved mathematical problem, e.g. testing for Collatz conjecture: https://math.stackexchange.com/questions/2158713/show-that-the-collatz-conjecture-would-be-provable-if-we-could-solve-the-halting/2158730#2158730 as previously mentioned at: https://boardgames.stackexchange.com/questions/24435/is-magic-the-gathering-a-consistent-game/24738#24738
This comes close to the "indefinite infinite loop" type rules, but I could not find an exact rule that covers this case in either:
- comprehensive rules of 2019, notably "104. Ending the Game"
- tournament rules, notably "4.4 Loops"
The indefinite infinite loop idea was mentioned at: https://boardgames.stackexchange.com/questions/24435/is-magic-the-gathering-a-consistent-game/24438#24438 and one notable example were the forbidden probabilistic skips of Basalt Monolith / Mesmeric Orb in the Four Horsemen combo deck:
- http://www.starcitygames.com/magic/standard/25043-Indefinite-Infinite-Loops-At-SCG-Legacy-Open-LA.html
- http://www.starcitygames.com/events/coverage/deck_tech_four_horsemen_with_j.html
- https://www.youtube.com/watch?v=3HVXvZl-PsI Pleasant Kenobi has talked about it after rules were made more explicit
but the Turing Machine loop is of a different kind however, since you:
- don't need, and can't to take any actions once the process is kick started
- if Collatz conjecture were false, the loop wouldn't be infinite our take an unknown number of actions to happen, we would know exactly when it stops
I would add a new tournament rule phrased as:
It is forbidden to put the game in a state where players have no choice , and no judge in the room can determine if the match ends in a draw or win / loss in a reasonable amount of time.
Of course, this is not ideal, because in general it relies on players estimating how much mathematics judges are likely know, and there could be more legitimate gray cases in the future, but we'll have to wait for those to come up.
Also in this particular example, the player who starts such a loop had infinite mana and drew their entire deck, so one may argue that winning the game would have been trivial before the machine was started, so some judges could consider this particular case to fall under slow play.
I would also like to see what happens if someone does this on MTGO, but once again they likely have or would add a trigger limit of some sort, and I'm not sure if it is possible to set things up to automatically pass over all your steps, otherwise players would run out of time eventually due to the seconds that pass between you clicking "move to the next step".
But who knows. Maybe this is just the motivation a smart judge was needing to finally solve Collatz? ;-)