
What is 5D chess? - searchableguy
https://en.chessbase.com/post/what-on-earth-is-5d-chess
======
hokumguru
I bought this game a few weeks ago with a friend and we jumped in without any
prior knowledge about the game or how it worked. After about 3 hours we were
finally starting to understand the basic principles and I have to say wow,
it's an absolute blast to play. Many hours in now we've finally begun
developing our own strategies and it's absolutely insane. I have to say that
5D Chess is one of the most creative and innovative games that I've played in
recent memory and I highly recommend it.

~~~
feider
What is your opinion on how into the chess one needs to be to get a similar
kind of experience out of the 5D chess? Asking as a casual hobby player.

~~~
xstas
I'd say you need to be comfortable with how the rules of chess work, but you
don't need to be a chess player. The time travel rules even out the playing
field for amateurs who play against actual chess players.

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mxwsn
'From my experience playing a few games on it against decently strong
opponents has been that at high levels it becomes "Chess, but it's much much
easier to checkmate, and 2~3 times a game some time travel shenanigans
happen."

The main reason for that is time traveling and dimension hoping come at a
tempo disadvantage. When you create a new timeline, you make 1 move, but give
your opponent 2 moves. You used your turn in the present, and created a new
board where it's their turn in the past.

Any time travel or dimension hops need to be worth twice as much, minimum, as
a normal move to even consider making them.

It does have more depth than normal chess, but it's not infinity deep. I still
love it. My biggest concern with high level chess matches is that many, many
games end in draws. It feels like it's impossible to a draw a gam e in 5D
chess' [0]

[0]
[https://www.reddit.com/r/Games/comments/hxqo6d/how_to_play_5...](https://www.reddit.com/r/Games/comments/hxqo6d/how_to_play_5d_chess_with_multiverse_time_travel/fz8nnqh/)

~~~
gwenzek
> You used your turn in the present, and created a new board where it's their
> turn in the past.

Doesn't it depend on the piece you use? Knights and Bishops seems to be able
to move on the board and move back in time at the same time.

~~~
Doxin
Pieces have the same movement rules as normal chess. A knight for instance
moves 3 spaces along one axis, and 1 space along another axis. If you time
travel you're essentially sacrificing one of those spatial moves for a
temporal move. For example 2 spaces back in time and 1 forward. So while it's
not entirely giving up a move it's fairly close, especially for pieces that
only move along a single axis at a time.

------
zw123456
I always thought a cool chess variant would be quantum chess where you can
move a piece to more than one square and assign a probability to each
position. Your opponent could do the same. But I never worked out how it could
work from there.

~~~
jaggirs
A players mental representation of the game is already that (and you use this
mental representation to predict future outcomes).

If you add probabilistic moves, the optimal way to play would be to give each
alternative move the same weight (ie probability) that you think it will win
you the game. You would pull this probability out of your mental
representation.

Something like, "I think this is the best move, but this one is really good
too so I will do it as well".

So I guess it could be fun to be able to try out all the moves you think are
good in this way. But then an easier way to achieve this is to just play the
game normally and go back to an interesting previous position once you have
won.

But maybe a set of rules that will allow you to still win the game 'in
retrospect' after all the 'best' moves were played by going through all the
alternative superpositions as well.

So basically just play normally, but when you doubt what move is best, you
make a superposition (and assign probabilities), which means you will be going
back to this position later.

The winner would be the one who won most often, with each win weighed by the
probability of that outcome (calculated based on the assigned probabilities
along the game).

Sounds like fun.

~~~
zw123456
Yes exactly what I was thinking, it is as if you mentally picture and weight
each move, but what if you could actually represent that somehow and play out
all the variations of a game like a multiverse. Sometimes when I play against
a computer I will try different things by trying something then going back
using undo, but then I wonder, wait maybe the other fork would have worked
out, etc. This way you could have many versions going at once. I have look at
source of various open chess engines and they do something similar, the idea
is what if there were a way, maybe with shading of the pieces or some other
way of representing the super positions of each possibility. The UI would be
interesting challenge.

~~~
em-bee
for the UI, how about duplicating the board? each game starts with one board.
at each split point the active board is duplicated and you can play each. at
the end you could draw a tree to show all the decision points and the end
positions.

for extra fun if one board gets to a position that another board already had,
the tree could be merged again.

------
YeGoblynQueenne
Interesting. When I read "5d chess" I thought it would be a game where each
dimension is represented by a different chessboard giving you a different view
of the game. So for example, in the first dimension, the white king is in 1a
and a black rook is in 2b, whereas in the second dimension the white king is
still in 1a but the rook is in 1b, thus threatening the king. So everytime you
make a move in one board, the piece you moved moves on all boards, but in a
different, but relative, position. So the point of the game would be to make a
move in one board that crated an advantage on another board- if a piece is
captured in any board, it's captured on all boards and if a mate is threatened
in any board it's threatened on all boards (and yeah, that's totally cribbed
off the kernel trick in SVMs: map a lower-dimensional space onto a higher
dimensional space to find a separating hyperplane that doesn't exist in the
lower dimensional space). I guess that would get very hard to play very
quickly though, certainly for a full game on an 8 × 8 board, but it could
perhaps be played in end games like KRK or simplified chesses like hexapawn
etc.

Btw, for anyone who likes time travel paradoxes, do watch Dark. It's up there
with Primer, but does your head in more because of how many characters there
are.

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sixstringtheory
The video at the end reminded me of "Imagining the 10th dimension"
[https://www.youtube.com/watch?v=8Q_GQqUg6Ts](https://www.youtube.com/watch?v=8Q_GQqUg6Ts)

So is this basically visualizing the tree of possibilities from any board
configuration, overlaid on itself at nodes where different sequences of moves
can result in the same board configuration, allowing you to "jump" to a
different "timeline" through the 5th dimension?

~~~
gliese1337
Oh my gosh, I _hate_ that "10th dimension" video _so freaking much_. It has
done nothing but spread confusion and false understanding across the internet.

If it were just presented as a fun exploration of what 10 dimensions _could_
be, for fictional purposes, it would be... OKish, I guess. But choosing "10"
specifically makes people erroneously think that this is what string theory is
about, which is completely wrong.

Additionally, it falls into the trap of assuming that curvature requires a
higher dimension to curve in, and that nontrivial connectivity inherently
requires such curvature, both of which are false and hard enough to explain to
people who have not been explicitly taught wrongly already.

And on top of all of that, it perpetuates the faulty idea that "the" 5th
dimension, or "the" 10th dimension are sensible concepts, by presenting its
particular choice of dimensions to discuss and its particular choice of
ordering of those dimensions as fact.

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shp0ngle
From all the descriptions, this is actually 4D, no?

Normal chess is 2 dimensions, plus you have time dimension (3D), plus you have
parallel timelines - that always go just one dimension

So it's 4D and not 5D?

edit: yeah it's actually "just" 4D, from the explainer here

[https://imgur.com/a/XyRJmuh](https://imgur.com/a/XyRJmuh)

~~~
87zuhjkas
It depends in real life you always have a 3D chess board (+ time dimension)
and in some chess UIs you have the option to get a 3D board rendered, like in
chessbase
[https://de.chessbase.com/Portals/All/2017/_eng/products/frit...](https://de.chessbase.com/Portals/All/2017/_eng/products/fritz16-18b-3dboard.jpg)

~~~
einr
But you actually only play the game in two dimensions, because the pieces
cannot move up or down. Normal chess is a game happening on a 2D plane whether
or not the representation of the board and pieces is 2D or 3D.

~~~
87zuhjkas
No, because that again depends on the representation. You can store the
information of moves and chess position in 1D. As for example, two players can
play a game of chess just by exchanging moves via morse code.

------
dasb
Great, now I can suck at chess in 3 more dimensions.

~~~
Yuioup
Just wait till somebody invents 5d Go

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TheOtherHobbes
How do you know if you have won? Or is it about avoiding checkmate in all
possible timelines for all possible time travelling moves?

~~~
treis
I'd think the same way you know you won regular chess. You capture the
opponent's king. Checkmate is just an acknowledgement that the current player
has no way of avoiding their opponent from taking their king on the next move.

~~~
aplummer
So checkmate in any one timeline counts? You couldn’t do all timelines.

~~~
learnstats2
I suppose you would have to avoid the king escaping to another timeline?

~~~
nsilvestri
You do , which is why it ends up being easier to attack kings in the past.
Because you can't change the past, only create new timelines, attacking a king
from any previous board state means that the attacking piece must be captured.

~~~
asa4akj
does this means that attacking the starting king position will always put the
king in check of the very first board? but, he can't really escape that

~~~
xstas
Yes, but it's not that easy. Pieces still make threats according to their
movement rules, whether through time or space.

For example, if your king moves from its square and an enemy rook attacks its
starting position (rooks can move any number of squares in any one direction),
then it's mate unless you can take the rook. However, if in the intervening
time, another piece lands on the same spot, then it will block subsequent rook
checks through time on that square.

------
miloignis
It looks amazing, and I really want to play it, but however I count I only end
up with 4 dimensions. A chess board is 2D, time back-and-forth is 3D, and
going up/down across universes is 4D. What's the 5th? Are they counting real-
life-time as the 5th? In which case normal chess is 3D, which seems like an
abuse of terms.

~~~
neop
It's only 4D. I believe they called it 5D chess because they didn't want
people to interpret this as 3D chess + time. If I recall correctly, the
tutorial mentions at some point that the 5th dimension is "unused".

~~~
kmill
It would have been nice if 4D only ever meant four spatial dimensions, and
then we'd have (3+1)D for three spatial dimensions and a time dimension. (And
(2+2)D for two spatial and two time dimensions :-))

~~~
prionassembly
2+2=4D could be for _position_ and _momentum_ in two dimensions.

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dihedral
We skipped right over the opportunity for non-integer fractal dimensional
chess! In all seriousness, this looks super interesting. I’d love to see some
live gameplay of it.

~~~
jerf
Arguably, that's what this is. The bifurcating timelines are better thought of
as n-dimensional space. Describing the location of a piece requires a
description of the bifurcations, which won't be a fixed number of numbers but
will go up as the game progresses. Integer dimensions don't really cover this.

~~~
dihedral
Yeah, great point, the dimensionality of the game increases as it progresses.
I can't tell from the article, is there a bound on the number of parallel
board timelines that can run simultaneously? Theoretically, without a bound,
the dimensionality could increase indefinitely (there could be non-terminating
paths that loop between the same game states enabling an arbitrary number of
bifurcations).

------
kyleblarson
Would be interesting to see something like this with poker. There are some
interesting, high variance games becoming increasingly popular and this would
certainly be a cool wrinkle: "6 card high low Omaha with time travel".

------
searchableguy
3d chess is another popular variant: [https://wikipedia.org/wiki/Three-
dimensional_chess](https://wikipedia.org/wiki/Three-dimensional_chess)

Lot of games you could spin up in this manner. I wonder if we are going to do
that for all the board games with tried and old strategies. HN has any
suggestions on what those board games should be?

Game on steam:
[https://store.steampowered.com/app/1349230/5D_Chess_With_Mul...](https://store.steampowered.com/app/1349230/5D_Chess_With_Multiverse_Time_Travel/)

There is a discord linked in the game help menu where people are discussing
lot of things including how to create a bot.

For the lazy: [https://discord.gg/8kQhp6](https://discord.gg/8kQhp6)

Edit: removed mobile url.

~~~
ansible
> _3d chess is another popular variant:_ [https://wikipedia.org/wiki/Three-
> dimensional_chess](https://wikipedia.org/wiki/Three-dimensional_chess)

I was crazy enough as a high-schooler to actually build (with the help of my
father) a 3D chess "board". It was mostly plywood, with eight 8x8 boards
stacked vertically. I had previously gotten a "3D" chess board which was just
three 8x8 boards. They weren't making Star Trek tri-dimensional chess sets
back then.

With the 8x8x8 3D board, movement rules for 2D chess have a "natural"
expansion to 3D, with only a few corner cases. White player's non-pawn pieces
start out on the bottom board, with the pawns on the next board up.

In practice, it was hard to visualize how the game was going in general. We
were constantly standing up and crouching to see. Only one of my friends
wanted to play, and he only lasted about half a game. :-(

With the failure to interest my friends, I had intended to write my own chess
program to play it. I had started out with the 2D version, and was then
intending to expand it later. The original was written in BASIC... and that
did not go too well.

~~~
nicoburns
I imagine it'd be quite hard to trap your opponent with an extra dimension to
escape in. Perhaps the board should be smaller to compensate. Regular (2d)
Connect 4 is played on a 6x7 board. But 3d Connect 4 is played on a 4x4x4
board.

------
cptroot
Happy to see this finally getting some traction on HN. I finally finished all
of the puzzles a couple of days ago and I'm confident I'm going to file this
one under the same file as Go: Fun to play, but even better to watch more
skilled players analyze.

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dilippkumar
I desperately want to go hang out on a forum where people are building AI bots
to play this game.

~~~
skavi
according to searchableguy, that’s happening right here:
[https://discord.gg/8kQhp6](https://discord.gg/8kQhp6)

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xwdv
I’d love to see a chess variant where you could move pieces upside down to the
bottom side of the board and make moves and pop back up onto the surface at
strategic points. Lurker chess.

~~~
searchableguy
Shogi?

[https://wikipedia.org/wiki/Shogi](https://wikipedia.org/wiki/Shogi)

------
ThreeFx
This looks amazing! Although I wouldn't be surprised if this was a forced
first-player win.

~~~
BbzzbB
Perhaps at an expert level, but given theory debt of even normal chess I
hardly see how this could be an issue at very expert level but that's not for
some years (assuming it gets a community but it clearly has a good start). It
actually looks really fun, hopefully there isn't a way to cheese-win as white,
but barring that it looks really fun and creative.

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keyle
When I was learning about puzzle game making, one of the rules was people
don't like puzzles. They like puzzles but not the feeling like they're doing
one.

This is kind of the opposite. So it really competes with Fall Guys then...

~~~
nsilvestri
Outer Wilds does the whole "puzzle game without feeling like one" better than
any other game I know.

~~~
egypturnash
God that game is SO GOOD. It gave me a lot of “I finished a puzzle” feeling
without having to do any hard puzzles for a lot of it, until the point where I
had to take a thing from the Hourglass Twins to another part of the system
without fucking it up, with suddenly higher stakes. I stopped playing it for
like a week when I knew that was what I had to do, because I had to be in the
right mood...

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throwawaynothx
Blackjack version, "Hit me.... ok stay"

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Yhippa
I watched the video at the end three times and still couldn't figure it out.

~~~
searchableguy
Try
[https://www.youtube.com/watch?v=eqMEiBu4M1c](https://www.youtube.com/watch?v=eqMEiBu4M1c)

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fileeditview
Would love to see some GM stream this. Go Nakamura :)

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throw1234651234
90 comments and no Putin joke yet?

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pmarreck
Now I can "checkmate, bitches!" in another timeline... This is tremendous

~~~
dane-pgp
I think that's called "Nothing personnel, kid".

[https://knowyourmeme.com/memes/teleports-behind-you-
nothing-...](https://knowyourmeme.com/memes/teleports-behind-you-nothing-
personal-kid)

------
otoburb
Lichess[1] is a popular site to play chess online for free. They offer
different chess variants to play against other people. Would be great if 5D
chess was one of the variants to play online.

[1] [https://lichess.org/](https://lichess.org/)

