GrandChess

GrandChess is the ultimate upgrading of Chess in 3 dimensions, with the same rules of the 2-dimensional chess game but a much greater degree of complexity. This is indeed a game fit for the GrandMasters' minds.

There are 512 cubic boxes instead of 64 squares. 128 grand-pieces for each player instead of the 16 pieces. The GrandChess framework contains 24 planes that are equivalent to a chessboard. Each grand-piece is positioned on 3 such planes; you can move it on any of the three chessboards; so playing a GrandChess game is very much similar to playing a simul on 24 chessboards against a single opponent.

Huge numbers of opportunities, positions and variants. An immense space opening up for larger openings theory. In Chess you can reach 400 different positions after White and Black's first move. In GrandChess the positions are 40,000 only after first move. 

Some people say Chess is going to be "solved". I.e. one day a chess engine, a learning machine or quantum computer will tell us that the starting position is a win (or a draw) whatever we play. Playing chess will then loose any interest. It'll only be a matter of memorizing the right sequence.

This is my gift for free to all Chess enthusiasts. So if Chess will ever be solved you can go on playing GrandChess while the engines are going to have indeed a hard time solving this one too.

Here are some explanatory videos, but the rules are the same as Chess: https://www.youtube.com/channel/UCOeIXNTxzW_IC1T1Mlxolew/videos 

Only exception: castling is made in two moves (pre-castling and castling), due to the three dimensions.

Waiting for good programmers who can make it onto online platforms and maybe we will play it on Chess.com too.

Nice realisation, congrats for the handwork. I'm just curious, how long do you need to set up the game? And how many moves typically in a real game between two players? The difficulty of course being to constraint the King to checkmate him. This is a common hurdle for 3D-chess, yours is a bit easier as there is no 3D-diagonal moves, but, still, it remains quite difficult to achieve in my opinion. How many games have been played?

Very interesting questions from a technically expert and savvy person, Jean. I answer you in two posts.

My idea is 20 years old, but realization is very recent: the result of lockdowns. Two people can assemble the framework in 10 minutes and arranging the grandpieces shouldn't take more than 2 minutes; but I think it should stay mounted on a table, maybe at a chess club. However I have already another model in project, more elegant and simple to assemble, all made in plexiglass. Moving pieces can take more time and care than in chess, but with long kitchen tongs you can do it precisely, without messing up the grandpieces. Anyhow all these times are reduced to zero hopefully creating a virtual animation, or playing on online platforms.

The physical model seen in the videos is a prototype. Only a handful of physical games have been played, but they are not significant because you need to train people's minds in parallel with the development of the game. At first it's like going back to when you were a kid, trying to play chess for the first time; where you feel lost in an ocean of combinations and miss out on lots of opportunities. The game needs to be tried by people who can handle 24 chessboards at once. Those are Masters and GradMasters. I submit the game hoping they will accept the challenge, maybe for fun, knowing that it's not easy for them psychologically.

You should approach this game like Chess is primary school and this is university. GrandMasters dedicated their whole life to chess, achieving an enviable position. I understand it cannot be easy to take on a challenge where everything you know, even for a chess grandmaster, is primary school compared to the university.

Perhaps the testing and refining work requires help from technically experienced people like you. Why not?

About constraining the king and game duration, please see the next post.

This is not the first 3-D chess proposal in history; but I think it's the first with such a great number of pieces. I believe that the secret for game's operability belies in proportions. In chess's starting position the pieces occupy exactly one half of the chessboard: this also occurs in GrandChess. It's important that the sheer number of pieces and their strength stands in the right proportions with the available space. Previous problems for 3-D chess where due to too much free space compared to the number of pieces. Here you have 128 of them cooperating in unison to constrain the opponent's king.

Another important proportion is the strength of the king compared to that of other pieces and to their combined strength. We can roughly measure the strength by the number of accessible squares; so in chess the maximum numbers are: K = 8, Q = 27, R = 14, B = 13, N = 8, P = 2 + 2. In GrandChess they are: K = 18, Q = 60, R = 21, B = 39, N = 24, P = 4 + 2

The strength ratio between the pieces of the two games is as follows: Q/q = 60/27 =  2,22; R/r = 21/14 = 1,5;  B/b = 39/13 = 3;  N/n = 24/8 = 3;  P/p = 6/4 = 1,5

In contrast the strength ratio for kings is K/k = 18/8 = 2,25; while the average of strength ratios between the other 5 pieces is 2,244444444. In practice they are balanced on the same number

So, as a mere matter of calculations, the combined strength of pieces constraining the king is balanced with the king's own strength in GrandChess the same way as in Chess. This makes me confident that an average game should have the same duration as a chess game. Nonetheless, I believe that even if it reached double duration, in my view it 'd be worth it.

Thank you for these answers. It makes a lot of sense. Compare to some other 3D-chess you have limited the moves (if I well understand) with no 3D-diagonal (I mean moves from corner to corner of cells) and this make the game more playable indeed. 
By asking on the duration, I was not criticising, just trying to quantify. I do love some very large (2D) chess variants where we have easily 200 moves. Keep going with your idea :=)

Thank you

Jean-Louis, I wanted to create a game that had to be the upgrading of Chess, only enhanced to the three dimensions; but remaining as similar as possible to chess. I realised that every move should be made on a chessboard, that is on a plane made of 64 squares. GrandChess has 24 such planes inside it. Thus people who are used to play chess will find this quite natural.

Allowing moves on the 3-dimensional diagonals would have denaturalized the game, because that way you don't move on a chessboard. Moreover, that gives excessive strength to bishops and queens. Or else you should create other types of pieces performing that kind of moves.

It's a matter of sticking to the chess model and maintaining the balance of forces.

Wikipedia says what people write in it.

If you like, you can write now there exists another GrandChess which is 3-dimensional and written in one word, without a space in between

Not very smart to confuse people by giving a new game the same name as a decades old and quite popular existing game, though...

That looks confusing as hell.

This is 3D-GrandChess, OK? Is everybody happy with that?

Alas people do not care of what have been done before them nowadays. It looks like nobody never open a book anymore, even never try to google to see what others have done. There is Grand Chess, there was also many Grand Chess in history of chess variants, Grant Acedrex and many shatranj al-kabir which literally mean the same thing.