Increasing the size of a chess game...

This is not meant to be heresy. Had a few thoughts about changing the basic chess game by increasing it's size and therefore it's complexity too. We all know a standard chess board is 8x8 squares and uses one set of pieces. How about increasing that to 16x8 squares and using two sets of pieces.

The board would be rows A-P. With two sets of pieces side by side. Or even use 4x chess boards equivalent. A 16x16 square board with four sets of pieces. The pieces would be set up two sets wide and two sets deep. This would increase the complexity of the game exponentially. 

The objective of the game would be to mate AS MANY KINGS AS POSSIBLE. Since there would be four kings each side. 

It's not heresy. It's a variant. There are many others who have had similar ideas.

Some of them have even had new game boards and pieces made.

Thanks. Seems I am behind in my awareness of 'variants'. Will do a bit more reading.

The problem with most variants is that they make the game bigger. Maybe more complicated. But not better. Fundamentally, the game is not better than Chaturanga was. 

I think it will be fun. I also think you must lookup shogi.

I'ts japanese chess

Basic is 9X9 but there are many variants

4*5

5*5

8*8

19*19

The fun there is also there is not only 1 king but also a Prince. Almost any piece can promote. Not only the pions

ex rook become dragon

And sorry to all woman; no queens

Usual issues with *large* board chess variant designs.

1. There are too many slow pieces. It's quite annoying to play on a 16x16 board with a horde of standard FIDE pawns. Especially if they're all doubled or tripled like in some setups. Other pieces such as the King, Ferz, and especially Wazir suffer significantly from slow move patterns.

2. Pawn openings can become quite weak. Pieces are faster.

3. You need to think carefully about how piece values change in the design. On the standard 8x8, a knight is equal with a bishop. On a 16x16 with only 64 pieces, the board is both much larger and much more open. Knights take 10 moves to cross it diagonally. They are a very slow piece and the ability to hop a single row of pawns doesn't even begin to make up for their poor movement pattern. This changes the opening to what is essentially a very complex Q + B endgame in a vast space with the ability to move more pieces in over time. Knights might still be worth 3 pawns. Maybe even 4 or 5. But bishops are worth much more than knights.

To make something that feels like chess, I think you will need to be very careful in what you put on the board and where. And probably add some fairy pieces and do something to restrain heavier leapers from rushing to the center.

Right, the main takeaway here is "chess doesn't work the same at all scales and board densities." You still almost surely not be able to just place copies or scalings of the standard FIDE board and call it a day unless you want some rather strange gameplay where pawns and leapers are irrelevant and the objective is to rush the middle with sliders to set up a checkmate from afar.

 Large variants with only orthodox pieces usually do not work very well. For rectangular boards a large width is not as detrimental as a large depth, though. A small depth increase (e.g. to 10 or 12 ranks) can be remedied by starting the pieces more forward, either leaving an empty rank behind those, or allowing multiple ranks of pieces behind the Pawns. Of course boards need not be square; there exist good variants on 12x8.

One problem with large variants with many pieces is that games tend to become long and boring. Leapers might not be useful for attacking if they take too many moves to cross the board, but they are surely good for defending. So sliders alone have little chance to achieve a checkmate, and to have a chance for winning you must go through the tedious process of engaging your leapers in the attack.

Also note that promotion plays an essential role in chess-like games. Without it you could heap up all your pieces around your King in a corner; no way anyone could break through such a defefense. But promotion makes that you have to protect your entire baseline, and the King is not your only vulnerability.

One problem with large variants is that strong pieces tend to deploy quicker, and get traded out of the game easily. Leaving you with hordes of slow-moving and boring pieces, which you have to grind away before getting anywhere near a checkmate. The historically successful large variants (mostly Shogi variants) either have pieces that count as 'weapons of mass destruction' (e.g. Fire Demons in Tenjiku Shogi can capture up to 8 pieces in a single move, by 'burning' all adjacent enemies), which do enough damage before they are traded. Or they somehow protect the strong pieces by having extra rules that forbid their trading. (Have you ever tried to play Chess with the extra rule that Queens cannot capture each other? Or that any piece capturing a Queen promotes to Queen?)

What about boards of infinite size with the pieces at each end (infinitely far apart)?

It has the same dynamics of only sliders being useful to attack.

I'm not sure you'd want to fill the board an uncountable infinity wide with pieces, however. That might be too many and make it hard to know whether the king is in check for example. Keeping the number of pieces finite, and certainly not uncountably infinite, increases sanity.

Because the finite-range pieces will be in a good location to defend their King, it seems to me such a variant would be a dead draw.  An additional problem is that you need a comparatively large amount of material to checkmate a King on a board without edges.

It is interesting that the ability to force checkmate on a bare King on boards of arbitrary large size is not the same as being able to do it on a quarter-infinite board.

Yes. It's actually kind of mindboggling the material needed to Checkmate on a full infinite board. A king and two rooks MIGHT be able to, but I'm not sure if it could be forced, since coralling the kings into position should be pretty hard.

It's also kinda surprising that a quarter infinite board doesn't work just like a large board.

The point is that on any finite board the strong side can always get the bare King between a corner and its own King, by simply walking the latter to the center. On a quarter-infinite board you can never catch up with a bare King that runs away from the corner if you weren't further away from the corner to begin with. And not every combination of pieces would be able to confine the bare King without help of their own.

BTW, I think KRRK on an infinite board is pretty simple. Just confine the bare King between two parallel Rook lines, the Rooks protecting each other. Then use your own King just outside these lines to drive the bare King towards the Rook. As soon as he takes opposition, use the Rook closest to your King to check him. And he has to take opposition when he reaches the Rooks.

There exists a variant with an infinite board.

yes i agree with american naviary

hmmmm