4 ms·

I was thinking about how Magic the Gathering has so many infinite combos. In a deck with a wide variety of cards, you're likely to be able to accidentally const

I was thinking about how Magic the Gathering has so many infinite combos. In a deck with a wide variety of cards, you're likely to be able to accidentally construct an infinite combo. For those who don't play, the most iconic infinite combo involves two cards, the first says "Whenever you gain life, an opponent loses that much life.", the second card says "Whenever an opponent loses life, you gain that much life." These cards, when combined, do nothing... until you gain a life or an opponent takes damage. Then their effects combined means a chain reaction that repeats until your opponents are dead and you have gained as much life as they had. There's a variety of infinite combos in MTG. Some of them involve a creature that says "Tap to add mana to your mana pool" combined with another card that says "Pay mana to untap a creature", allowing you to tap and untap an infinite number of times. Some infinite combos involve returning a card to your hand, and recasting it which gives you the resources you need to return it to your hand and recast again. Some infinite combos involve looping a card from your discard pile repeatedly. There are no one-card infinite combos (that would likely not make it past the testers), but there are plenty of two-card infinite combos, and an combinatorically increasing number of three and four card infinite combos. I think there is some similarity computationally speaking between turing completeness, and the ability to construct an infinite combo in a game like MTG. An infinite allows you (the player) to continue taking the same action over and over again, accumulating some game resource in the process. This bears resemblance to the infinite tape Turing envisioned, a way to hold data. Player actions are much analogous to the instruction set. Infinites that are optional for the player (not all infinites in MTG are optional once the pieces are on the board) can also stand in for conditional statements - a key requirement of turing completeness. I'd be interested in seeing the bare minimum number of cards required to generate turing completeness. If anybody else knows more about this domain, I would love to hear their opinions.

Severian 3y ago
Please correct me if I'm wrong, but I thought an infinite combo that doesn't require user at interaction results in a draw. So your first example would be this, but the tapping one isn't. It's been years since i played however.
- swagasaurus-rex 3y ago
  Infinite combos that require the player to opt into repeating an action will not end in a draw, because the player is expected to decide on the number of times the combo will repeat for. Infinite combos that not optional but win you the game instantly, like the sanguine bond + exquisite blood combo I mentioned earlier, means you just win. Infinite combos that are not optional but do not win you the game result in a draw.
  - pierat 3y ago
    > Infinite combos that are not optional but do not win you the game result in a draw. There's the 'donate an unsacrificable islandhome creature to an opponent who has no islands'. Infinite amount of state based checks happen that are unavoidable, and cause the game to draw.
- dmorgan81 3y ago
  It depends. If the game state changes, say like a change in one player’s life total, then the loop won’t usually end in a draw. In the example above the opponent will eventually die. In paper once a player has demonstrated a loop they must choose a number of times to repeat the loop and then the game is fast forwarded to the chosen end state. For example, a player might execute a loop that could gain them infinite life, but really they must choose a point to stop. Usually that player will choose 1,000,000,000,000 or another “essentially infinite” value and the game moves on. There are infinite loops that can draw the game, but in a tournament game if one player can take an action that would end the loop, say by destroying one of the loop pieces, that player must take that action. Only if no player can end the loop does the game end in draw.
  - thom 3y ago
    Is that true? If your opponent creates a loop but you have a spell that can end it, I don’t believe you’re compelled to cast it if you decide the draw is more favourable. Definitely don’t like that rule if it exists.
thom 3y ago
For what it’s worth, it’s currently vintage cube season on Magic Online and you can draft a deck with multiple infinite combos without much effort. Sadly you have to do all the clicking so you might run out of time. Paper magic is much kinder because once you’ve demonstrated a loop you can basically assign infinite damage, gain infinite life, create infinite creatures etc without having to play it out.
- jacksontheel 3y ago
  What's funny is that after demonstrating the loop you still have to give a concrete number of times that you repeat it. You can't deal infinite damage, but you sure can do a googolplex damage.
  - A_D_E_P_T 3y ago
    Why go for such a small number? Raise Graham's Number to the power of itself -- at the very least. https://research.phys.cmu.edu/biophysics/2021/01/09/nobody-comprehends-grahams-number https://research.phys.cmu.edu/biophysics/2021/01/09/nobody-c... I'm sure it can be entertaining to try and deal the largest possible finite amount of damage, which requires finding uncommonly large numbers.
    - tromp 3y ago
      Raising Google's Number to itself doesn't make it appreciably bigger. Instead you can pick TREE(3), or SCG(13), or Loader's Number which is about the largest famous one we know how to compute. Beyond that there's the likes of Busy Beaver numbers and beyond that is Rayo's number. Btw, Graham's Number is less than BB(49 bits) [1]. [1] https://codegolf.stackexchange.com/questions/6430/shortest-terminating-program-whose-output-size-exceeds-grahams-number/263884#263884 https://codegolf.stackexchange.com/questions/6430/shortest-t...
wwilim 3y ago
My favourite combo ever was infinite 5/5 dinosaurs
throwaway743 3y ago
You just described my Vampire deck, using Vito and Exquisite Blood. Personal favorite is Squirrel's Nest + Earthcraft. Coat of Arms is optional fun lol
cbsmith 3y ago
https://commanderspellbook.com/ https://commanderspellbook.com/
vikingerik 3y ago
> There are no one-card infinite combos There are. Basalt Monolith has "tap: add 3 mana" and "3 mana: untap". It doesn't actually have any net effect without some other card triggering on that or modifying it somehow, but it actually can do an infinite number of actions by itself as one card.
- swagasaurus-rex 3y ago
  Obligatory "we finally broke basalt monolith" This card is a staple for so many infinite combos because, just like you're saying, it adds mana (the biggest restriction to pulling off broken effects), and it can be an engine for any number of complimentary effects that trigger off tapping or untapping or reducing costs or copying triggers.

Severian 3y ago

Please correct me if I'm wrong, but I thought an infinite combo that doesn't require user at interaction results in a draw. So your first example would be this, but the tapping one isn't. It's been years since i played however.

swagasaurus-rex 3y ago
Infinite combos that require the player to opt into repeating an action will not end in a draw, because the player is expected to decide on the number of times the combo will repeat for. Infinite combos that not optional but win you the game instantly, like the sanguine bond + exquisite blood combo I mentioned earlier, means you just win. Infinite combos that are not optional but do not win you the game result in a draw.
- pierat 3y ago
  > Infinite combos that are not optional but do not win you the game result in a draw. There's the 'donate an unsacrificable islandhome creature to an opponent who has no islands'. Infinite amount of state based checks happen that are unavoidable, and cause the game to draw.
dmorgan81 3y ago
It depends. If the game state changes, say like a change in one player’s life total, then the loop won’t usually end in a draw. In the example above the opponent will eventually die. In paper once a player has demonstrated a loop they must choose a number of times to repeat the loop and then the game is fast forwarded to the chosen end state. For example, a player might execute a loop that could gain them infinite life, but really they must choose a point to stop. Usually that player will choose 1,000,000,000,000 or another “essentially infinite” value and the game moves on. There are infinite loops that can draw the game, but in a tournament game if one player can take an action that would end the loop, say by destroying one of the loop pieces, that player must take that action. Only if no player can end the loop does the game end in draw.
- thom 3y ago
  Is that true? If your opponent creates a loop but you have a spell that can end it, I don’t believe you’re compelled to cast it if you decide the draw is more favourable. Definitely don’t like that rule if it exists.

thom 3y ago

For what it’s worth, it’s currently vintage cube season on Magic Online and you can draft a deck with multiple infinite combos without much effort. Sadly you have to do all the clicking so you might run out of time. Paper magic is much kinder because once you’ve demonstrated a loop you can basically assign infinite damage, gain infinite life, create infinite creatures etc without having to play it out.

jacksontheel 3y ago
What's funny is that after demonstrating the loop you still have to give a concrete number of times that you repeat it. You can't deal infinite damage, but you sure can do a googolplex damage.
- A_D_E_P_T 3y ago
  Why go for such a small number? Raise Graham's Number to the power of itself -- at the very least. https://research.phys.cmu.edu/biophysics/2021/01/09/nobody-comprehends-grahams-number https://research.phys.cmu.edu/biophysics/2021/01/09/nobody-c... I'm sure it can be entertaining to try and deal the largest possible finite amount of damage, which requires finding uncommonly large numbers.
  - tromp 3y ago
    Raising Google's Number to itself doesn't make it appreciably bigger. Instead you can pick TREE(3), or SCG(13), or Loader's Number which is about the largest famous one we know how to compute. Beyond that there's the likes of Busy Beaver numbers and beyond that is Rayo's number. Btw, Graham's Number is less than BB(49 bits) [1]. [1] https://codegolf.stackexchange.com/questions/6430/shortest-terminating-program-whose-output-size-exceeds-grahams-number/263884#263884 https://codegolf.stackexchange.com/questions/6430/shortest-t...

wwilim 3y ago

My favourite combo ever was infinite 5/5 dinosaurs

throwaway743 3y ago

You just described my Vampire deck, using Vito and Exquisite Blood. Personal favorite is Squirrel's Nest + Earthcraft. Coat of Arms is optional fun lol

cbsmith 3y ago

https://commanderspellbook.com/ https://commanderspellbook.com/

vikingerik 3y ago

> There are no one-card infinite combos There are. Basalt Monolith has "tap: add 3 mana" and "3 mana: untap". It doesn't actually have any net effect without some other card triggering on that or modifying it somehow, but it actually can do an infinite number of actions by itself as one card.

swagasaurus-rex 3y ago
Obligatory "we finally broke basalt monolith" This card is a staple for so many infinite combos because, just like you're saying, it adds mana (the biggest restriction to pulling off broken effects), and it can be an engine for any number of complimentary effects that trigger off tapping or untapping or reducing costs or copying triggers.