The Search for the Longest Infinite Chess Game

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  • Опубліковано 27 кві 2024
  • We explore extremely long Infinite Chess games, starting with Mate in Omega, and progressively climbing to higher and higher transfinite ordinals!
    Play Infinite Chess at: www.InfiniteChess.org
    Support me and its development on my Patreon, and get your name in the credits of my videos: / naviary
    Join the Infinite Chess Discord server: / discord
    Access the spreadsheet board editor: docs.google.com/spreadsheets/...
    \/ Credits for the positions shown, along with links to learn more about them! \/
    Omega, Omega^2, Omega^3 by Joel Hamkins and C. D. A. Evans: math.colgate.edu/~integers/og2...
    Omega*2 by Noam. D. Elkies: mathoverflow.net/a/63841/514442
    Omega^4 by C. D. A. Evans, Joel Hamkins, and Norman Lewis Perlmutter: math.colgate.edu/~integers/rg4...
    Omega_1 Proof by Matthew Bolan: mathoverflow.net/questions/63...
    Subscribe to his channel! / @matthewbolan8154
    Some clips are from Joel Hamkins presentation, “The theory of infinite games, including infinite chess”, watch it here! • TMWYF: The theory of i...
    See more presentations on The Infinite Games Workshop: / @infinitegamesworkshop...
    Note for the chapter “Climbing the Ordinal Tower”: I often mention “this to the power of this infinitely…”, or “infinite epsilons above this…”. When I word things like this, what I really mean is to take the limit, or supremum, as we approach doing that operation infinitely. I have chosen this wording to make things more intuitive to the viewer and those who may have zero ordinal arithmetic knowledge. This chapter is not meant to be a detailed explanation of ordinal arithmetic.
    🎶 Music used (in order) 🎶
    Background Check by David Robson: • Detective Music For In...
    Looking For Clues by David Robson: • Suspenseful Detective ...
    Witness Testimony by David Robson: • Mysterious Detective B...
    Viking by Aakash Gandhi: • Viking - Aakash Gandhi
    Mario Bava Sleeps In a Little Later Than He Expected To by Chris Zabriskie: • Mario Bava Sleeps In a...
    This is licensed under a Creative Commons Attribution 4.0 license. creativecommons.org/licenses/...
    Source: chriszabriskie.com/vendaface/
    Artist: chriszabriskie.com/
    Anime Song 2 by Montage of Chips: • Anime Song 2
    Music: True Detective by Soundridemusic
    Link to Video: • Suspense Detective, Cr...
    White Hats by Wayne Jones: • White Hats - Wayne Jones
    Artemis by Scott Buckley - released under CC-BY 4.0. www.scottbuckley.com.au
    Video: • 'Artemis' [Inspiration...
    Needle In A Haystack by David Robson: • Investigation Crime Sc...
    Signal to Noise by Scott Buckley - released under CC-BY 4.0. www.scottbuckley.com.au
    Video: • 'Signal to Noise' [Cin...
    Weirder Stuff by Geographer: • Weirder Stuff - Geogra...
    Many of these songs are provided by FesliyanStudios! Make a donation to also gain access to their music :) www.fesliyanstudios.com/policy
    Chapters:
    0:00 Introduction
    1:18 The Game Tree
    3:21 Omega
    5:17 Why Ordinals?
    8:04 Omega+1
    8:58 Omega*2
    10:41 Omega^2
    12:27 Omega^3
    14:48 Omega^4
    20:20 Matthew’s Proof
    24:09 Climbing the Ordinal Tower
    26:53 Conclusion
    Other stock footage is from Pixabay.com
    If I missed, or incorrectly gave credit, please don’t hesitate to contact me using my email! Located in the "About" section of my channel, click "View email address".
  • Ігри

КОМЕНТАРІ • 1,4 тис.

  • @WolfgangShaffer-ey6ce
    @WolfgangShaffer-ey6ce 2 місяці тому +1893

    Imagine being foolish enough to blunder checkmate in ω^3•10+ω^2•8+1001

    • @Naviary
      @Naviary  2 місяці тому +338

      🤦‍♂️ "You blundered! How could you not see that?"

    • @godofnumbersakausername5226
      @godofnumbersakausername5226 2 місяці тому +97

      @@Naviary Imagine being foolish enough to blunder checkmate in phi(psi(W^W^W^W^eZw^w^(w^2)*2),0,n0,23,193)
      PS: W is capital omega, w is lowercase omega, e is epsilon, Z is zeta, n is eta

    • @JaredJeyaretnam
      @JaredJeyaretnam 2 місяці тому +41

      @@NaviaryYou fell for one of the classic blunders!

    • @mahinchess
      @mahinchess 2 місяці тому +35

      Hikaru be like:..... Yes that's checkmate in (imagine the amount of all real numbers)

    • @mrt_pose
      @mrt_pose Місяць тому +6

      Rookie error lululul

  • @bruhmcbro2704
    @bruhmcbro2704 3 місяці тому +3152

    I love how you start with something that resembles chess and end with massive structures designed only to prolong the inevitable.

    • @Patashu
      @Patashu 2 місяці тому +130

      The lower quadrants have been lined with bishop cannons of increasing size

    • @ianweckhorst3200
      @ianweckhorst3200 2 місяці тому +28

      And yet, a math brain loves it

    • @meks039
      @meks039 2 місяці тому +3

      thats such a good way of describing how my brain is reacting to this.

    • @edgeman1135
      @edgeman1135 2 місяці тому +34

      That awkward moment when you blunder into an infinite number of rook locks...

    • @mongoose7857
      @mongoose7857 2 місяці тому

      Just like real life

  • @dazcar2203
    @dazcar2203 2 місяці тому +1683

    the moment terminology turned to "towers" and "cannons" i think this stopped being about chess

    • @kruje314
      @kruje314 2 місяці тому +99

      'What is this piece?'
      'Tower.'
      'ITS CALLED DA ROOK'

    • @erka339
      @erka339 2 місяці тому +68

      Tower is also a valid terminology, it is the name of the rook in many languages, also cannon is the name for the rook equivalent in Chinese chess although it moves differently, in this video's case the cannon name is appropriate to me as the rooks go as fast as a cannonball !

    • @Proto-EXX
      @Proto-EXX 2 місяці тому +33

      soon we’re gonna have nuclear warfare in chess if we keep goin higher with these ordinals

    • @tigerghg7302
      @tigerghg7302 2 місяці тому +24

      Those massive structures weirdly remind me of the game of life

    • @dazcar2203
      @dazcar2203 2 місяці тому +12

      @@tigerghg7302 chess has become cellular automata

  • @gavinlol-lo1pd
    @gavinlol-lo1pd 2 місяці тому +1438

    A higher game value does not necessarily mean the game will take longer, but instead it means your opponent can be more annoying

    • @richardpike8748
      @richardpike8748 2 місяці тому +34

      It does beg the question, how long could a game last if black tried to play _as badly_ as possible? I.e. trying to get itself checkmated

    • @eeeee11235
      @eeeee11235 2 місяці тому +18

      @@richardpike8748 2 move mate

    • @eeeee11235
      @eeeee11235 2 місяці тому

      ​@@richardpike8748 ig depends on position

    • @londegel
      @londegel 2 місяці тому +14

      ​@@eeeee11235 not in infinite chess, since the king can just move backwards

    • @catcatmagee
      @catcatmagee 2 місяці тому

      E

  • @paperwhite3853
    @paperwhite3853 3 місяці тому +1365

    It's kind of beautiful, that two kings are just having a staring contest, while all of this is happening

    • @icantthinkofaname8139
      @icantthinkofaname8139 2 місяці тому +96

      Bet after the 198,298,171,372,287,394,291th move they would wish they could just lunge at each other and have a fist fight

    • @fntthesmth423
      @fntthesmth423 2 місяці тому +70

      Typical monarchy forcing everybody else to dedicate their lives to them lol

    • @whannabi
      @whannabi 2 місяці тому

      The UK has no problem with that. Sucking money like leeches. Very impressive.​@@fntthesmth423

    • @RFM__
      @RFM__ 2 місяці тому +4

      shout out to their patience because doing absolutely nothing all of that amount of time is huge‼️‼️

    • @abdillahahmad7025
      @abdillahahmad7025 2 місяці тому +7

      "Now, now, there's no need to fight... why not settle this over a nice cup of tea?"

  • @WillySalami
    @WillySalami 2 місяці тому +615

    Oh man, I really hate when I'm just casually playing and suddendly Stockfish tells me I have a mate-in-Omega-1 minus 1 position.

    • @gianglai7346
      @gianglai7346 2 місяці тому +22

      Omega-1 minus 1 is just Omega-1

    • @barrianic4
      @barrianic4 2 місяці тому +15

      @@gianglai7346actually omega-1 minus 1 is ill-defined

    • @aaravthediscoverer
      @aaravthediscoverer Місяць тому

      @@barrianic4 actually omega-1 minus 1 is e =m2

    • @barrianic4
      @barrianic4 Місяць тому +2

      @@aaravthediscoverer omega-1 does not have an imediate predessessor because it is a limit ordinal

    • @aaravthediscoverer
      @aaravthediscoverer Місяць тому +1

      @@barrianic4 but does it have an immediate successor?

  • @tails183
    @tails183 2 місяці тому +399

    Of all things, I never thought I'd hear the phrase "bishop cannon" in my life.

    • @DR-7
      @DR-7 2 місяці тому +7

      BROTHERS! WE NEED TO CRUZADEEEE

    • @glowstonelovepad9294
      @glowstonelovepad9294 2 місяці тому +9

      I searched "bishop cannon" and apparently there is someone who is a bishop and named Cannon.
      en.wikipedia.org/wiki/William_Ragsdale_Cannon

  • @vnXun
    @vnXun 2 місяці тому +659

    26:13 After infinitely many levels of incomprehensible infinity, we finally reach SMALL Veblen ordinal, what a journey to reach something that's literally called small.

    • @-minushyphen1two379
      @-minushyphen1two379 2 місяці тому +41

      That’s because it is still countable (there is a one-to-one correspondence between its elements and the natural numbers). ε_0, mentioned in the video, is also countable, and ε means small in maths. So it is also “small”, in the sense of still being countable.
      The real numbers are uncountable, so there are more real numbers than announcements and types of announcements in Infinite Chess.

    • @liam.28
      @liam.28 2 місяці тому +27

      @@-minushyphen1two379the large veblen ordinal is also countable

    • @kruje314
      @kruje314 2 місяці тому

      bruh

    • @thefastmeow
      @thefastmeow 2 місяці тому +3

      that's what she said before she left me

    • @MichaelDarrow-tr1mn
      @MichaelDarrow-tr1mn 2 місяці тому +6

      @@-minushyphen1two379 the large one is also countable

  • @louisjagger2177
    @louisjagger2177 3 місяці тому +505

    The later stages begin to resemble Conway's Game of Life :)

    • @Naviary
      @Naviary  3 місяці тому +129

      In some ways it does resemble it doesn't it?

    • @subscheme
      @subscheme 2 місяці тому

      Well yes because of the nature of forced mates restricting the moves when assuming optimal play, choice is lost and it becomes a cellular automata which is very interesting

    • @shauas4224
      @shauas4224 2 місяці тому +77

      @@Naviary now I'm thinking if infinite chess is Turing complete

    • @T11235
      @T11235 2 місяці тому +6

      It's the game of life, except it's more complex

    • @mathgeniuszach
      @mathgeniuszach 2 місяці тому +3

      @@shauas4224 I wonder that too now

  • @Steamworker_Evolair
    @Steamworker_Evolair 2 місяці тому +162

    I went in expecting a relatively standard chess video, i was not expecting you to basically recreate Vsauce's "how to count past infinity" video within the language of chess. That was an absolutely incredible watch, i applaud you on your efforts!

  • @gasgg
    @gasgg 3 місяці тому +248

    I've finally found an area where transfinite ordinals are useful

  • @Henry3.1415
    @Henry3.1415 3 місяці тому +195

    The intro with the infinite chess game zooming out to show the text is so cool

    • @findystonerush9339
      @findystonerush9339 2 місяці тому +3

      3.1415? Pi? 3.14159 this is pi followed by!

    • @Silence_now
      @Silence_now 2 місяці тому

      @@findystonerush9339fun fact pi is TINY it has a lot of digits but it is small because it starts a with 3 so if you round down in 3

  • @Mika-lt6lr
    @Mika-lt6lr 3 місяці тому +205

    Man i’ve not once left a comment on a UA-cam video ever, but this vid was actually just too incredible too not praise you for. This almost makes me want to try and construct an omega^5 (and higher) position. Great video as always man.

    • @Naviary
      @Naviary  3 місяці тому +17

      Thank you, I really appreciate it!

    • @objectshowfan362
      @objectshowfan362 2 місяці тому +17

      We've seen how far we can go with infinitely many pieces, but how far can we go with only finitely many pieces?

    • @Naviary
      @Naviary  2 місяці тому +32

      @@objectshowfan362 This is still an open question! We know so far that omega^2 is possible.

    • @TymexComputing
      @TymexComputing 2 місяці тому

      Yeah - i am sure that many of the 4000 Grandmasters wouldnt like to deliberately analyze this knowledge - still i am sure that if i played infinite correspondence chess and i trained on ω tactics there would be someone who learned the whole set of ω^2 and would beat me i wouldnt know how :)

    • @Unknown-vg2mf
      @Unknown-vg2mf 2 місяці тому +3

      @@objectshowfan362 It is bounded by Church-Kleene ordinal (the first nonrecursive ordinal, also the supremum of the recursive ordinals)

  • @abellematheux7632
    @abellematheux7632 3 місяці тому +283

    It's important to understand that there is an ordinal (omega^CK, Church-Kleen ordinal) lower than omega_1 (noted as capital omega in the video) that is no longer recursive (i.e. it can't be reached by the construction shown in the video).
    As a result, the plateau required for an omega^CK mate is strictly incalculable. In other words, there's no way to describe the position of the pieces unambiguously ("describe" in an algorithmic sense).
    As a result, mankind will never know a mate in omega^CK (however, all smaller mates are feasible).
    Edit : In the replies to this comment, there are some very pertinent remarks for you to read, including a reply from Matthiew.
    ( PS: Incidentally, no program would be capable of calculating a sequence of mats whose ordinals tend towards omega^CK (otherwise, we could use them to construct omega^CK mats). In other words, it can be shown that there is a mate shorter than omega^CK that mankind will never be able to achieve because of the computability of the Universe.
    The meaning of a non-recursive ordinal is very difficult to grasp in this context, since we're dealing with such large infinities that the consequence of what I'm saying is not perceptible. )
    ( I'm using a translator to express myself, as I'm French and the terms are getting a bit technical, so I hope it's still intelligible. )

    • @matthewbolan8154
      @matthewbolan8154 2 місяці тому +41

      Among computable positions (once you precisely define computable positions) omega^CK is an easy upper bound, and my construction suffices to show you cannot do better. If you do not ask the position to be computable, then for any countably branching well-founded tree my construction gives a position with game value equal to the rank of the tree, so all countable ordinals indeed occur as game values of some (not necessarily computable) position.
      In fact, we can say a little more. Given as an oracle a function f:N -> N such that the image of f is well ordered under the Kleene-Brouwer ordering and of order type alpha, my construction shows that there is a position, computable relative to f, with game value alpha. This shows that restricting to positions of any level of the lightface Borel hierarchy (e.g. computable, Sigma_2, arithmetic, hyperarithmetic, etc), the correct upper bound is the supremum of all ordinals belonging to that level.

    • @neopalm2050
      @neopalm2050 2 місяці тому +18

      You can describe it. You just need to reach beyond anything equivalent to the standard turing machine operations to do so. Non-computability doesn't stop the busy beaver function from being expressible. You just can't write a program that generates them (or even prove what numbers it outputs past a certain point).

    • @abellematheux7632
      @abellematheux7632 2 місяці тому +6

      I will edit my comment tomorrow if I don't forget (it's night here).

    • @TymexComputing
      @TymexComputing 2 місяці тому +1

      Thank you - its a very informative comment :) - heard about cardinals and ordinals , little and big omega notation but really missed the Calvin-Klein definitions (intentional typo). I am really not sure what do you mean by "computable" - someone referred to turing machine idea but i have no issue with having a power of ω wide computer register or just write a sentence (function) that states i can browse the whole board in an instant and calculate the formula on it :). The universe has ONLY got 10^80 atoms, but the quantum deterministic wave function has been immersed in a Hilbert space i see no issue with saying that everything is achievable just by creating and idea and truly believe it :). Thank you!

    • @zaringers
      @zaringers 2 місяці тому

      Hmmm grave interessant ça aussi

  • @Naviary
    @Naviary  3 місяці тому +387

    This is what I’ve been working on the past several months! I couldn’t split the topic into more cliff-hangers on you guys, so here’s covering it all! By far my biggest project. I hope you enjoyed!
    Consider subscribing 😉 And come join the discord! discord.gg/NFWFGZeNh5

    • @treelol
      @treelol 2 місяці тому +4

      u have my respect

    • @wesleystoltz8421
      @wesleystoltz8421 2 місяці тому +2

      Would it be possible to reach a higher checkmate clock with custom made pieces?

    • @Naviary
      @Naviary  2 місяці тому +24

      @@wesleystoltz8421 Unfortunately not, with only countably many infinite squares on the board, you can never create a piece that can move to uncountably many squares, which would be required to reach Omega_1. The exception is you would have to create a piece that can make infinitely complex moves (like, chain infinitely many moves into a single move). Infinite Checkers has this property, and can reach uncountable ordinals!

    • @Patashu
      @Patashu 2 місяці тому +10

      @@Naviary Ok now I need to see the video on infinite checkers 👀

    • @arcaltoby5772
      @arcaltoby5772 2 місяці тому +2

      In Infinite Chess, you could get a position Mate-in-ω_1 if there is infinite pieces on the board. This has been already proven. Although, with only a finite piece, you can't make a position with Mate-in-ω_1. Keep in mind that some Mate-in-x position have the value of x greater than ω_1^CK.

  • @neopalm2050
    @neopalm2050 2 місяці тому +285

    It is possible to get mate in ω₁. Just not in any actual chess board. All you have to do is give the board to the opponent and tell them they have to set up a board in which you have the winning move. They have access to every countable ordinal move count, and so the move counter when you give them the board is ω₁.

    • @neopalm2050
      @neopalm2050 2 місяці тому +86

      However, you have to give them infinite time to set up such a board. Unfortunately, if you restrict yourself to the boards that can be represented by a bounded amount of information, this is suddenly a countable ordinal again. You must afford them a literal eternity to make this particular announcement for it to truly be mate in ω₁. They have to _actually be able to spend this eternity_ in order for it to work. If you just afford them an unbounded amount of time, you force them to make an announcement that decides between a countable set of countable ordinals (each being the best they can do if given n years), which is just not good enough.

    • @danielyuan9862
      @danielyuan9862 2 місяці тому +18

      Ordinals are so trippy sometimes. I suppose if you let the opponent to set up the chessboard, it would be "mate in omega_1", since omega 1 would be the smallest ordinal greater than all the others.

    • @danielyuan9862
      @danielyuan9862 2 місяці тому +7

      ​@@neopalm2050If you give someone time to set up a board, is each moment an announcement because you have to go at a finite speed, but there's no limit to how fast you can be, unless you account for the speed of light. But there are probably ways to set it up so the same thing happens but without that nuance.

    • @neopalm2050
      @neopalm2050 2 місяці тому +5

      @@danielyuan9862 I was imagining a situation where the only real announcement would be the actual board state. Anything done up to that point, they could take back. I was also assuming there was an upper bound on how often information can be set (information that determines the board state).

    • @angelmendez-rivera351
      @angelmendez-rivera351 2 місяці тому

      What you are describing is not a mate-in-ω(1) at all. Indeed, what you are not describing is not even infinite chess to begin with.

  • @maximdegi
    @maximdegi 3 місяці тому +129

    the moment of history, the third naviary's video

    • @BabayChannel
      @BabayChannel 3 місяці тому +14

      Only countably many videos until the ω-th video

    • @parapasarunbuenrato8773
      @parapasarunbuenrato8773 2 місяці тому +2

      Unlike **some company**, he actually know what comes after 2

  • @arandomdiamond2
    @arandomdiamond2 2 місяці тому +34

    This is a great way to explain infinity. Most people don't understand it but starting from something that we can feel and showing that it can get beyond anything we can imagine yet still never reach true infinity is very satisfying.

    • @user-oh6pw7bx4q
      @user-oh6pw7bx4q 2 місяці тому +1

      People misunderstand than the "infinity" that shows up in most conversations about infinity isnt actually infinity its actually absolute infinity wich is the last number before we enter the realm of imaginary numbers

  • @stanimir5F
    @stanimir5F 2 місяці тому +23

    At 15:05 Hikaru be like: pf that's a simple forced mate in ω⁴ position.
    Joke aside: that ω⁴ was very entertaining to watch!

  • @eliascastillojerez6778
    @eliascastillojerez6778 3 місяці тому +48

    10:58 Tier 2 announcements were a plot twist I wasn't expecting. Great video and great narration!

  • @tsevasa
    @tsevasa 3 місяці тому +124

    Insanely well made! This truly is a game for the gods and we have only begun to scratch the surface :)

    • @Naviary
      @Naviary  3 місяці тому +14

      Thank you!

    • @RickMattison314
      @RickMattison314 2 місяці тому

      @@Naviary, I tried joining the Discord, but it said that I'm unable to accept the invite.

    • @Naviary
      @Naviary  2 місяці тому

      @@RickMattison314 That's weird. It should work! Maybe try a different link? discord.gg/bWbgYqX7Re

    • @RickMattison314
      @RickMattison314 2 місяці тому

      ​@@Naviary, still nothing.
      Edit: NVM. It worked on my phone.

    • @Naviary
      @Naviary  2 місяці тому

      @@RickMattison314 Great!

  • @cobble616
    @cobble616 2 місяці тому +49

    This was such a good video, the ending sort of reminded me of 17776, and how the people in that story play thousand years games of football. I could also imagine them playing those really long infinite chess games

    • @steeevealbright
      @steeevealbright 2 місяці тому +4

      I had this exact thought about Jon Bois

    • @beyondobscure
      @beyondobscure Місяць тому

      Never heard of that before. It's great!

  • @AGamerNamedSky
    @AGamerNamedSky 2 місяці тому +34

    "we can have a game length of any number we desire, even exceeding the time in seconds until the heat death of the universe. we just have the move the rook that many spaces away" is such a crazy and hard ass sentence

  • @kevincsellak296
    @kevincsellak296 3 місяці тому +64

    This is honestly one of the best mathematics videos I've seen on youtube. The only thing that could be considered missing, in my opinion, is mention of the difference between cardinal exponentiation and ordinal exponentiation; it'd call back to the "least ordinal greater than all finite ordinals" from before, while giving some context to why omega^omega is still countable while 2^aleph_0 is no less than the cardinality of omega_1. I don't think there's any good place this could fit within the video (because you went on to very concisely describe all countable ordinals), and seen as you did a great job with the script, I don't think adding it would make the video better than it currently is, but it did come to my mind. Can't wait to hear more come from this project in the future!

    • @Naviary
      @Naviary  3 місяці тому +5

      Thank you

    • @Naviary
      @Naviary  2 місяці тому +19

      If there's one thing I would have included more, it honestly probably would have been greater explanation of ordinal arithmetic! You are correct with the script being a little tight, not sure where I could have paused the story to explain arithmetic. More videos will come!

    • @abellematheux7632
      @abellematheux7632 2 місяці тому +2

      2^aleph_0 is the cardinal of a set of applications from a set of cardinal 2 to a set of cardinal aleph_0, such as bit sequences. A sequence of bits contains an infinite amount of information.
      You'll notice that all the elements of omega^omega are written with a finite amount of information. So it's more analogous to the set of finite bit sequences (wich is countable).

    • @angelmendez-rivera351
      @angelmendez-rivera351 2 місяці тому +1

      @@abellematheux7632 This is inaccurate. A sequence can be encoded entirely with finite information only, using a recursion. In fact, trying to think of cardinality as being about information begin with is incorrect.

    • @abellematheux7632
      @abellematheux7632 2 місяці тому

      ​@@angelmendez-rivera351
      I denote F^E the set of applications from a set E to a set F.
      Let beth_n be the (ordinal) sequence of cardinals such that beth_0=alef_0 and beth_{n+1}=2^alef_{n}. Let X be a set of cardinal beth_{n}, and the set 2^X={0,1}^X is of cardinal beth_{n+1}. More generally, let E be a set of finite cardinal, E^X is of cardinal beth_{n+1} like 2^X.
      Finally, if X is not in bijection with a set of the form 2^Y, then X is in bijection with a union of sets all of lower cardinal than X and all of different cardinalities. For example, the union of sets X_n of cardinal n has cardinal beth_0.
      All elements of omega^omega can be written with a finite amount of information, i.e. with a finite number of characters in a finite alphabet. However, the number of characters per element is not bounded.
      If there is no way to represent the elements of omega^omega by sequences of characters in a finite alphabet such that the number of characters is bounded, then omega^omega is not finite (obvious). However, omega^omega is in bijection with a set included in the set of finite sequences of possible characters in this alphabet. By denoting this alphabet E, X is therefore in bijection with a subset of the union of E^n, making it a set of cardinal beth_0.
      2^beth_0, in turn, is in bijection with a set of the form 2^X.
      In E^X with finite E, I like to call E the alphabet and its elements characters when I'm vulgarizing. So, to compare infinite sets that look like E^X, just compare the cardinal of E. I like to call the cardinal of E the amount of information needed to write the elements of E^X. It's as if, for f belonging to E^X, we wrote, for each x belonging to X, f(x).
      Of course, this is a vulgarization procedure. In reality, we don't really write down this amount of information. But it does help to recognize the size of a set: the elements of R are written with beth_0 decimals, those of R^R with beth_1 reals (which themselves are written with beth_0 "information"), and those of Q with a finite number of digits.
      I really hope I've made myself understood. It's probably just a misunderstanding of my intention and the way I use the words "sequence" and "information".
      I don't blame you for criticizing me, of course, and you can tell me if I wasn't clear.
      I'd like to point out once again that I'm very bad at English and that I use a translator, which can be a big source of misunderstanding.

  • @mrorcadood
    @mrorcadood 3 місяці тому +40

    Thanks for the tutorial, now I know how to deal with this when it comes up in my games!

  • @janaki3829
    @janaki3829 3 місяці тому +29

    8:04
    Oh hey, it's the Code Bullet song!

  • @EnerJetix
    @EnerJetix 2 місяці тому +25

    Even if I’ve watched Vsauce’s video on infinities that talks about larger ones, this video still blew my mind. To say this is well made is an understatement. Omega/10 video.

  • @christopherearth9714
    @christopherearth9714 2 місяці тому +6

    The worst thing in Infinite Chess is probably the Bishop sniping you from 45 multiverses away.

  • @aloysiuskurnia7643
    @aloysiuskurnia7643 3 місяці тому +35

    OOOOOOOH now I see how my confusion about omega + 1 from the last video gets resolved. It's very elegant!

    • @Naviary
      @Naviary  3 місяці тому +6

      Glad I could clear your understanding!

    • @Blue_FirewalI
      @Blue_FirewalI Місяць тому

      Please tell me why the big boss number at the end that can never be reached (omega 1) is also called OMEGA AND absolute infinity ​@@Naviary

  • @steeevealbright
    @steeevealbright 2 місяці тому +13

    20:26, pitch perfect delivery lolol

  • @user-gy8ff8xl2l
    @user-gy8ff8xl2l 2 місяці тому +13

    Imagine getting skewered by a bishop on the square b925836

  • @DoNotSin
    @DoNotSin 2 місяці тому +37

    8 by 8 chess is just 2 groups of children fighting (with a leader) and that GM's there is just super smart leaders.
    But infinite chess is THE REAL BATTLEFIELD between empires in the multiverse

    • @xaf15001
      @xaf15001 2 місяці тому +2

      Several universe died during 1 turn of Infinite Chess. The only epic chess battle you couldn't not miss.

    • @DoNotSin
      @DoNotSin 2 місяці тому +1

      @@xaf15001 you couldn't not miss?

    • @weare2iq376
      @weare2iq376 2 місяці тому +1

      @@DoNotSin Yeah, you had to miss it, you'd be dead long before turn 1 finished 🤣

  • @tektek1100
    @tektek1100 2 місяці тому +8

    started laughing at omega³, checked how much of the video is remaining, oh boy

  • @vinsovan9707
    @vinsovan9707 2 місяці тому +15

    The real question is why you'd sit through omega^4

  • @John_Gillman
    @John_Gillman 2 місяці тому +2

    i love how with this configuration you could hide a bishop extremely far away, get it onto position and then snipe the queen from 3 kilometers away

  • @wumaster1
    @wumaster1 2 місяці тому +3

    I love how you played a nuclear alarm in the background when talking about omega^4.

  • @user-zd4hr1vr7s
    @user-zd4hr1vr7s Місяць тому +9

    Why does this feel evil

  • @triplebog
    @triplebog 2 місяці тому +28

    This Omega principal is actually relavent to the game Magic The Gathering, and is inbuilt into the rules. Essentially, in that game, it's very possible to generate infinite loops and combos. In that scenario, the way the rules work is that once you demonstrate an infinite loop, you are then allowed to shortcut actually doing that loop N number of times, where N is a number of any size of your choosing. The "priority" is then given to your opponent, who can agree, or name a smaller number that they will choose to interrupt and intervene at if they have an action that can do so, which is rare after the first loop.
    Because of this, it's not extremely rare for monsters to end up with a billion power, or to give yourself a googol health, etc etc

    • @Naviary
      @Naviary  2 місяці тому +12

      I haven't played Magic, but that is actually quite interesting!! For certain actions it allows you to pick an arbitrary amount of steps to repeat that action?

    • @StriiderEclipse
      @StriiderEclipse 2 місяці тому +11

      The same is true for yugioh as well! They have the same rule of “demonstrate a loop once to show that it’s infinite and then declare how many times you are going to perform it”

    • @harleyspeedthrust4013
      @harleyspeedthrust4013 2 місяці тому +4

      so this is what the memes mean when they say that magic the gathering is turing complete

    • @Deh9o11en8or
      @Deh9o11en8or 2 місяці тому +3

      yeah you need to demonstrate both that you can create a loop, but also that you can choose to stop the loop, otherwise you either win, lose or draw game depending on the loop's effect on both players' life total

    • @AndrewBlechinger
      @AndrewBlechinger 2 місяці тому +2

      @@StriiderEclipse I thought they just banned cards that cause infinite loops? (Freaking Pole Position, man.)

  • @That-One-Frog
    @That-One-Frog 2 місяці тому +14

    I just had this idea: If we start with the normal arrangement of pieces, we have two rooks. And since the board is infinite, we can't promote our pawns! Well, most (almost all) of the positions shown here are impossible anyway lol.
    Great video! I loved it! I have always loved the concept of infinity. You got a sub!

    • @Naviary
      @Naviary  2 місяці тому +13

      Thanks! In competitive play, the current rules allow promotion at the normal ranks 1 & 8. But yes, for the positions I showed, there was no promotion, and pawns never have the opportunity to queen...

    • @crowreligion
      @crowreligion 11 днів тому

      But what about infinite chess 2, with infinite amount of pieces?

  • @_Epidemic_
    @_Epidemic_ 3 місяці тому +18

    Right as I was rewatching your previous videos you drop yet another banger, great work as always.

  • @GenTheFurredArtist
    @GenTheFurredArtist 2 місяці тому +3

    This is basically just what happens when you're really determined to NOT lose.

  • @willlllllliam
    @willlllllliam 2 місяці тому +6

    This seriously has to be one of the best videos I've ever watched. I normally don't ever leave comments but this deserves it. I was drafting a lot longer of a comment talking about all the little details between the script and the editing I noticed that made it great, but it was getting too long so I'll just say that I noticed them and leave it at that. Great video, ω/10 :)

    • @Naviary
      @Naviary  2 місяці тому +1

      Thank you. I tried to make it the best I could!! All the little details count.

  • @Dondoki_
    @Dondoki_ Місяць тому +2

    I imagine if there is an after which you are immortal in you just calling up your buddy and saying "Yo, are you down for a quick game of chess? ill set it up in the Omega to the power of 3 position."

  • @tdubmorris5757
    @tdubmorris5757 2 місяці тому +3

    Really looking forward to the in-game board editor. Thanks for the amazing vid! Mind is beyond blown with how complex these positions have to be

  • @chenivan6171
    @chenivan6171 2 місяці тому +4

    very well made! haven't seen anything that makes me so invested in quite a while. props to u!

  • @mastercrash0683
    @mastercrash0683 2 місяці тому +5

    Now make chess but pieces can move to decimal values of spaces instead of just whole numbered spaces, allowing for an infinite amount of spaces between each space.
    Eg inbetween the numbers 0 and 1 there are an infinite amount of decimals, so one could conceivably create an infinite amount of ordinal number checkmates between them

  • @Tovosx2
    @Tovosx2 3 місяці тому +4

    Bruh the editing and explanation is just too good 😭 Bro is severely underrated

  • @legendgames128
    @legendgames128 2 місяці тому +3

    Mate-in-Omega^4 reminds me of hostage situations in movies.

  • @truckjumperdude
    @truckjumperdude 2 місяці тому +6

    The way you explained this made it so simple to understand and still very interesting, this is a "5-tier" video 🙂

  • @sirsamiboi
    @sirsamiboi 2 місяці тому +3

    What an amazing video 😭❤ I love how it gradually went from normal-looking chess to the never-ending nesting of countable infinities using nodes and towers

  • @davethesid8960
    @davethesid8960 2 місяці тому +5

    This video shattered my brain but every second was worth it. Great explanation of ordinals!

  • @g1ug45
    @g1ug45 2 місяці тому +3

    Amazing video! As a member of the intersection in the venn diagram between chess and math I've really enjoyed it! Can't wait to see what other wonderful concepts you will show us in the future!

  • @Patashu
    @Patashu 2 місяці тому +9

    hell yes, I was waiting for this video to come out and it's every bit as good as I hoped
    Next things to explore:
    Mate in w^2 with finite pieces (may be possible to prove it's impossible to setup? but the fact that you can get w*n with arbitrarily high n in constant pieces makes it tantalizing...)
    Complexity class of/computers made in chess and chess variants

  • @Dieto2115
    @Dieto2115 2 місяці тому +5

    I didn't even notice that 29 mins had flown by. I wish you and your project all the best!

  • @5dnikita
    @5dnikita 3 місяці тому +13

    the best video!!! i am looking forward for w^w position

  • @jsdp
    @jsdp 2 місяці тому +2

    This is a great video and honestly a really good explanation of transfinite ordinals. Will recommend this to a fair few people, this is great. Best video i have watched on youtube in a while mate. Cheers and hope your day is going well whenever you read this.

  • @The4DRY4N
    @The4DRY4N 2 місяці тому +4

    i knew it would get REALLY wild when the bishop cannons appeared
    banger video! it's great to see how your video skills evolved with this infinite chess journey, and i'm all for it :D
    my only issue is the part of the ordinals getting """bigger""" feeling a bit too fast without a lot of the aritmethic context (and my brain doesn't help :P) but i see why you would approach it that way (on the bright side it makes me want to learn more about it so yay)
    anyways, Ω/10.

  • @pauls5745
    @pauls5745 2 місяці тому +3

    A couple years ago, I heard about a chess engine's analysis of a game showing in a certain position had a forced mate in 256 and was amazed at this concept. It's so far beyond that now?! All I can say is Wow!

  • @saulkay8674
    @saulkay8674 2 місяці тому +2

    I love how it is incredibly logical, some deep thinking and you will understand. Pretty great video

  • @InTheBeginningTheUniverseWas
    @InTheBeginningTheUniverseWas 3 місяці тому +6

    I love how it seems like there's a countably infinite number of named ordinals. Transfinite mathematicians have too much time... transfinite time it seems. And they love naming numbers!

    • @angelmendez-rivera351
      @angelmendez-rivera351 2 місяці тому

      There is only a countably infinite amount of objects which can be described in any formal language with a finite alphabet of symbols.

  • @Florragonis
    @Florragonis 2 місяці тому +6

    Get the camera Mom,
    Naviary just uploaded

  • @asj3419
    @asj3419 2 місяці тому +3

    I'm very interested to see how you are going to make infinite structures work. Your chessboard is obviously finite (the need for coordinates for storing the piece positions ensure that), but having structures that extend to the edges without taking up unfathomably large amounts of memory (or do so after the first move) sounds like a interesting challenge, especially with the complicated patterns these boards have. It sounds very possible, though.

    • @Naviary
      @Naviary  2 місяці тому +1

      I will need a chunk-like system, where I only have a finite area loaded at a time. Definitely a challenge, and a challenge to optimize it too!

  • @MeGaGiGaGon
    @MeGaGiGaGon 2 місяці тому

    Amazing video! I love the delving into the infinites of ordinals, and can't wait to see what you produce next!

  • @morapazfilgueira743
    @morapazfilgueira743 2 місяці тому +1

    Really liked this video! Very informative and educational without necessarily wanting to be that. Keep it up!

  • @raynorshine3388
    @raynorshine3388 2 місяці тому +3

    Unbelievably cool, I’m amazed by how much effort you put in - it was 100% worth it. Best of luck to you! Genuinely one of the best videos I’ve ever seen on this platform (as a chess player and set theorist I may be biased but still…)

  • @Robert-jy9jm
    @Robert-jy9jm 2 місяці тому +5

    This is a masterpiece! It may very well be the best video I have ever watched!

  • @droidanimado5803
    @droidanimado5803 2 місяці тому +3

    I've never seen so much dedication to a game of chess, good job (for leaving my brain in liquid form)

  • @apexcrocodile6264
    @apexcrocodile6264 2 місяці тому +1

    This is a fun gem of a channel. Really entertaining stuff keep it up :D

  • @decract
    @decract 2 місяці тому +8

    "I hate math"
    "I hate physic"
    "I hate chess"

  • @sleepykitten2168
    @sleepykitten2168 2 місяці тому +3

    This was an extremely well done video.

  • @TBTfantasyFish
    @TBTfantasyFish 2 місяці тому +1

    Stockfish: "1 missed win"
    The missed win:

  • @tomp6762
    @tomp6762 2 місяці тому +1

    I've been waiting for this video to continue the infinite chess saga, thanks!

  • @TactfulWaggle
    @TactfulWaggle 2 місяці тому +4

    Imagine white, after mate in Omega^4, all the hard work to get to the king, just statemates in the end

  • @decract
    @decract 2 місяці тому +3

    BROO I DIDN'T EVEN REALISE THIS CHANNEL IS NEW BUT IT IS REALLY GOOD 🔥🔥🔥

  • @1vader
    @1vader 2 місяці тому

    Damn, this is amazing, I watched a few videos about infinite ordinals and omega before but never really understood it properly. This made it so much clearer.

  • @romanvolotov
    @romanvolotov 2 місяці тому +1

    great content, thank you. it's unfortunate it takes sooo much time to make, i love your videos :<
    the world of infinity (or infinities probably) has always fascinated me.

  • @tiburonconb
    @tiburonconb 3 місяці тому +3

    FINALLY A VIDEO!!!! NAVIARY THE GOAT!!!!

  • @andrewwang2209
    @andrewwang2209 2 місяці тому +3

    Hey Naviary! This might be a stretch but I wonder if the mate-in-X could even be undecidable?
    We already saw in the mate in omega-4 how close each side was to winning.
    What if the game position represented the rules of a undecidable game?
    This whole video reminded me a lot of Sylver's Coinage, which itself is unsolvable rn. So I guess if you simulated that game in infinite chess SOMEHOW, it'd be mate-in- implication of math problem 🎉

    • @Naviary
      @Naviary  2 місяці тому +1

      I think so! Pretty sure if we were just handed a mate-in-omega1CK position, it would be impossible for it to figure that out, as it's non recursive and uncomputable, so it must be impossible to create an algorithm that can calculate the clock for every single possible position!

  • @TheArtOfBeingANerd
    @TheArtOfBeingANerd 2 місяці тому +1

    All the ordinal numbers were just blowing my mind. Not the size of them, but the fact that we have notation for it

  • @abtinhidaji9977
    @abtinhidaji9977 3 місяці тому +1

    What was this video? This was an excellent mixture of chess and mathematics. It taught me so many chess concepts... And then it blew my mind even more. The work that was done for this video is insane. Big shoutout to all mathematicians and programmers involved. Subbed.

  • @tomatetactico4641
    @tomatetactico4641 3 місяці тому +9

    I wonder what is the biggest mate-in-x we can reach with a finite amount of pieces. After all, you start a position with only 16 pieces, and you can only reach up to 10 of any given piece. How big does it get with this constraint?

    • @Naviary
      @Naviary  3 місяці тому +7

      That... is another story to tell! This one is actually still an open question. We don't know yet.... But we do know that at least Omega^2 is possible with finite pieces!

    • @crystallinnen5600
      @crystallinnen5600 8 днів тому

      @@Naviary❤

  • @tuures.5167
    @tuures.5167 3 місяці тому +6

    This is all very interesting, but since most of these positions require an infinite amount of material, what I'd like to know is, what is the longest (currently known) infinite chess game position that can be achieved from the regular starting position

    • @Naviary
      @Naviary  2 місяці тому +5

      As in the normal setup? Or any position allowed with finitely many pieces?

    • @tuures.5167
      @tuures.5167 2 місяці тому +2

      @@Naviary From the normal starting position. The setup can be implausible, that is, it can require one or both players to have played moves that are suboptimal or even nonsensical. But it should be _theoretically_ possible to get to the position from the normal setup.

  • @user-qd5yk1pp1x
    @user-qd5yk1pp1x 2 місяці тому +1

    I love this channel, although is is small, it is very insightful and interesting!

  • @andromeda9818
    @andromeda9818 2 місяці тому +1

    I love the nuclear bomb warning siren when it changes to a higher omega lmao

  • @matthewbolan8154
    @matthewbolan8154 3 місяці тому +8

    Hey look that's me.

    • @Naviary
      @Naviary  3 місяці тому +2

      Thank you for your contributions!

    • @tsevasa
      @tsevasa 3 місяці тому +2

      Minecraft youtubers are going crazy these days.

    • @lamshywy8920
      @lamshywy8920 2 місяці тому +1

      I am your new subscriber who found your channel from this video

  • @randomviever
    @randomviever 3 місяці тому +3

    You know it's a good day when Naviary uploads

    • @randomcat5262
      @randomcat5262 3 місяці тому

      Interspecies probabilistic union agrees

  • @foryoutubecomments2029
    @foryoutubecomments2029 2 місяці тому +1

    this was fantastic! any math youtube fan who understands or enjoys even a bit of chess will love your video, Naviary

  • @beanorama
    @beanorama 3 місяці тому

    I love your vids! You're awesome Naviary! Keep it up!

  • @anirudhv2215
    @anirudhv2215 3 місяці тому +13

    Can you make a video explaining the Mate in Omega^Omega (theoretical) mate please? 🥺

    • @Naviary
      @Naviary  3 місяці тому +7

      😉👍

    • @aav56
      @aav56 2 місяці тому +2

      ​@@NaviaryI would like to know as well! I feel like you kind of glossed over how exactly the higher order mates work in the bishop zugzwang position.

    • @Naviary
      @Naviary  2 місяці тому +2

      @@aav56 It's a little hard to understand. I would recommend reading up more on Matthew's proof himself. But basically there exists an algorithm that tells us exactly where to place the nodes to obtain the ordinal value we want. I briefly mention here that an w^w announcement would descend to an w^n position for any value n. An e_0 announcement would descend to w^w^w... for any height n. Basically any announcement of any size N can descend to any ordinal T that is included in the infinite sequence leading up to it.
      In the bishop tree, if we want to make higher ordinal positions, we can always just take existing trees we have made, and repeatedly place them as choices in the first branch of the tree. This will always give us higher ordinals.

    • @ihateyoutubehandles444
      @ihateyoutubehandles444 2 місяці тому

      ​@@Naviaryis it possible for an Omega^^Omega checkmate?

    • @Naviary
      @Naviary  2 місяці тому

      @@ihateyoutubehandles444 That's just written as e_0 (epsilon zero), and yes!

  • @nerf7778
    @nerf7778 2 місяці тому +3

    The mate in omega^4 would actually be omega^5. Your opponent can choose how long they would like to take to move.

    • @Naviary
      @Naviary  2 місяці тому +3

      "The original bishop moving up is the tier 5 announcement, each rook tower is a tier 4 announcement. Each pawn movement in the rook towers allows the activating of a bishop cannon tier 3 announcement. Each bishop fired from that cannon is a tier 2 announcement. And each gateway door threat it makes is a tier 1 announcement, deciding how long it will take before it moves!" 🤣

    • @ThunderClawShocktrix
      @ThunderClawShocktrix Місяць тому

      by that logic normal chess is omega*n where n is the number of moves in the game

  • @Johnnysboy3987
    @Johnnysboy3987 2 місяці тому +1

    I saw omega next to a chess board and felt like paul revere warning that the mathematicians are coming to take our safe space

  • @noahhuguenin3848
    @noahhuguenin3848 2 місяці тому +1

    HOW DID I NOT KNOW ABOUT THESE ORDINALS!!!?!!?! This is one of the most amazing things I've seen in my life, thank you for making this!

  • @AdrianHereToHelp
    @AdrianHereToHelp 2 місяці тому +8

    It feels like at some point you'd hit a problem of density, and higher ordinals would require more room than is afforded in just 2D space

    • @Naviary
      @Naviary  2 місяці тому +7

      It does feel like that though, right? More details on the proof can be found following a link in the description.

    • @FancyHalcyon
      @FancyHalcyon 2 місяці тому +4

      It feels like this a bit, but if you are about to run out of the room, I think you can double the spaces between each node. Since you can do it infinitely, you will never run out of the room

    • @HazhMcMoor
      @HazhMcMoor 2 місяці тому

      ​@@FancyHalcyonit seems like it'll only raise a tier instead of infinitely

  • @zionfultz8495
    @zionfultz8495 3 місяці тому +5

    If one were to develop continuous infinity chess, I believe a mate in (Big) omega 1 position would be possible. But likely the construction too psychotic for anyone to actually formulate

    • @zionfultz8495
      @zionfultz8495 3 місяці тому +1

      A way of making continuous chess would be to make each piece take a certain amount of area on the board, two pieces area can't overlap (Of course this would also correspond to captures), and a piece can move continuously on a line of its movement, excluding knights and kings. Blocking the movement of a bishop would happen on the point where if you move the bishop's area along its line it would overlap another piece. If this piece is the enemy's you can capture it on any point up to the point you leave its area. This also means you could make an arbitrarily small move, as well as an arbitrarily large move (In discrete infinite chess there is only the arbitrarily large)

    • @Naviary
      @Naviary  3 місяці тому +2

      How would continuous infinite chess work? Infinite checkers also has interesting properties, allowing game values larger than omega 1.
      EDIT: That is interesting!

    • @zionfultz8495
      @zionfultz8495 3 місяці тому

      Pawns can move continuously up to one of their areas length forward. Or two of them on their first move. And capturing works like a jump move, making it discrete (Otherwise it would break the rules of normal chess). En passant can be made, but is a bit weird

    • @Empika
      @Empika 3 місяці тому

      @@zionfultz8495 I made a game like that as a school project. Granted, since it runs on a computer, it's not actually continuous, but it's close enough lol

    • @subscheme
      @subscheme 2 місяці тому

      @@NaviaryWill you make a video on infinite checkers? or any other infinite game variants

  • @gunhasirac
    @gunhasirac 2 місяці тому

    This is truly remarkable. Thank you for putting all these together. This will be an incredibly good introduction to ordinals and how big omega_1 is. This has as much education value as entertainment value.

  • @ariflan
    @ariflan 2 місяці тому +1

    I recently found your video about infinite chess, I really liked it and looking at your channel I got very upset, because you haven't uploaded for months. But you just uploaded new video! I subscribed with notifications.

  • @nodrance
    @nodrance 3 місяці тому +10

    i don't think there's any other glyph that could have the same impact as Ω being the limit of all this. Like imagine if you got the top and the limit was like ι or something.

    • @Naviary
      @Naviary  3 місяці тому +7

      "ι" 🤣 I know... The other option was using ω_1 (with the 1 as the subscript), but I knew Ω would be so much cooler!!! Imagine a massive build up to a symbol that is just a dot • or something ordinary

    • @Polandball1138
      @Polandball1138 2 місяці тому +1

      Ig we can use big omega to be both omega1 and abs infinity, they have similar impacts on the transfinite, but different scales

    • @The360MlgNoscoper
      @The360MlgNoscoper 2 місяці тому

      Well, there's always θ.

  • @officiallyaninja
    @officiallyaninja 3 місяці тому +15

    Can't wait for continuous infinite chess next

    • @giuliosf
      @giuliosf 2 місяці тому

      It is a problem to define the moves of the King, pawn and knight, BUT I'm thinking we could use the cartesian square of hyperrintegers instead of that of integer, so we are not limited anymore below omega_1

    • @cultistaautista
      @cultistaautista 2 місяці тому

      Continuous infinite-dimension infinite chess with infinite -verse complex time travel

  • @CalCapone3
    @CalCapone3 2 місяці тому +1

    This video is making so many mathematical concepts make sense. What an incredibly, incredibly well made video. This is what youtube should be for.

  • @powerSeriesEX
    @powerSeriesEX 2 місяці тому +2

    imagine if it was almost checkmate but then you moved wrong and it is a epsilon omega

    • @Naviary
      @Naviary  2 місяці тому +1

      "How did you blunder mate in e_w? That was so easy to spot.."