Rated Comments

You should be able to do this by defining Pawn and Ferz as the first two pieces, setting maxPromote=2, promoZone=1, and promoChoice=W (assuming W is the ID of the War Elephant). It might still want you to indicate the 'choice' by clicking on the War Elephant in the table (which will then be highlighted in blue). But it only requires a choice when the table is opened anyway. If the table is closed it always promotes to the default piece, which is the first ID of the promoChoice string. If there is never any choice, there is no reason to open the table.

The Play-Test Applet doesn't offer an opportunity to specify a maxPromote parameter different from 1. In western Chess variants it is very rare that there is more than one promoting piece, and in the cases I knew the promotion rules for the non-Pawns are then often special. (E.g. more Shogi-like, where there is a fixed promoted form.) The Play-Test Applet has no provision for defining Shogi-type promotions (which would be controlled by the diagram parameters maxPromote and and promoOffset, rather than promoChoice.)

Such mixed promotion rules are not really supported by the Diagram proper; the Diagram can be augmented with a user-defined JavaScript function WeirdPromotion to handle such cases. This is what I used for Chess and a Half: as far as the Diagram is concerned only Pawns promote, and it enforces the promoChoice setting on those. Promotion of the other pieces is handled by having WeirdPromotion recognize when they should promote, and return the promoted version in that case. I also use that for implementing 'contageon' in Maka Dai Dai Shogi.

It is always a hard call what to include in an interface to keep it user-friendly; I don't want to deter prospective users with an enormous list of options they would almost never need.

I have been thinking for how the need for using a custom WeirdPromotion script could be reduced. I could for instance introduce a parameter contageon that would decare a list of pieces that should be treated as contageous, and by default make royal pieces immune to that. (Or also introduce a parameter immune.) And I could make mixed promotions standard by having the Diagram obey the promoChoice parameter for the first piece (presumably Pawn) even when promoOffset is non-zero, if the promoChoice is non-empty or different from a single +.

Very similar to Wagner Chess: https://github.com/brianthetall/wagnerChess

This page is 100% going to crash soon due to traffic from SUSD viewers!

This is an excellent chess variant, and is one of my favorites. I think it plays better than either of the games from which it is derived. The starting position is carefully considered, allowing a wide variety of different openings.

The rook should still be worth slightly more than the bishop on this board but it is very close. I performed the mobility calculation. With a 30% board occcupancy, the rook's average mobility is 9.8 whereas the bishop's is 9.2. And the mobility of the rook increases faster than that of the bishop as the board clears out.

The design of this game makes no sense to me. The Rook is upgraded to a Dragon King. The Knight is upgraded all the way to an Amazon. The Queen is upgraded to the most powerful piece I have ever heard of. But the poor Bishop is downgraded to a Wazir - a piece that moves only one step horizontally or vertically. One problem is that the board has so much power that it will be a tactical smash-fest. Another problem is that the Wazirs will never move. I cannot imagine any circumstance in which a player would waste a move on them, except possibly to get them out of the way to allow castling, and probably not even then. With all the nightriders, castling will likely be impossible anyway.

I once had a CV of my invention (Wide Chess) gently criticized for my adding to the standard chess army of each side (on a 12x8 board) 4 pawns, plus two pairs of leapers that were somewhat similar to each other, in that they both had an alfil movement as part of their powers. Namely, it was thought said leapers weren't divergent enough from each other.

In the case of (10x8) Royal Court, a pair of leapers plus 2 pawns is added to the army of each side. The leapers have the same movement powers as knights, plus they can also move like a man (often called the Centaur compound). So, I can see how this addition of leapers to the standard chess army might be gently criticized, too (at least they are very powerful leapers, which might relieve any perception of slight redundancy).

Recently I had a couple of ideas of my own about adding pair(s) of fairly knight-like minor pieces to the FIDE army, although I may have rejected these ideas too quickly, partly due to the previous critique (of my Wide Chess). Namely the ideas involved adding either a pair of fibnifs and/or a pair of horse(mao)-wazir compound pieces (depending on the board size I would use). Besides Wide Chess not yet proving popular on Game Courier, I'd add another inhibition I have is that I've seen very few examples on this website of the FIDE army plus pair(s) of pieces added to them, where the pair(s) were not strikingly divergent in some way from other piece type(s) used in the chosen armies. Indeed, Wide Chess and Royal Court are more or less the only counter-examples I've noticed.

https://www.chessvariants.com/piececlopedia.dir/fibnif.html

https://www.chessvariants.com/piececlopedia.dir/mao.html

It says KisO4 in the list, which is correct, but I didn't update that one. I had guessed that it defaulted to that based on the board size. But I didn't put the king on the board either - it starts there (if that matters.)

I updated those values and now castling works correctly too.

This is VERY impressive. It is now possible to make presets for typical variants with no writing of GAME code at all. Thank you for making this!

This is a fantastic game and one that I regularly enjoy playing both with friends or on my own. When playing on my own I change clothes after each move, speak in a different accent and have a different personality/backstory to give the appearance of separate players. Anyway I digress, a fantastic game, enjoy.

Another piece I wonder if it ever was used is Nao

very interesting have noticed this when i was collating material on renaissance chess some time ago , didn't realise there's an actual different version of chess, thank you for the page Renaissance Chess

New information on this thread: Another copy of this chess set has been found in an online posting on Board Game Geek!  Follow this link and scroll down to see the photo and comments: https://boardgamegeek.com/geeklist/276021/item/7825120#item7825120

Sadly this set is also missing the rules!  But I am attaching my most recent ruminations on what the rules were when I played the game in my youth :-)

Viking Chess Rules as best as they can be remembered – November 28, 2020

The goal of the game is to checkmate your opponent's king as in regular chess. 

Board: The board is made up of "rings" linking "crosses" (the spaces).  There is a centre space, the “star”, in the middle. 

Pieces: There is a king, 2 rooks (flat tops), 2 bishops (spikes) and 4 pawns per side.

All pieces start off the board.  

On their first turn (white goes first) each player places their king anywhere on the board on any space except the centre space (I believe that no piece could start on the centre star because it gives too much of an advantage to start there - but I am not 100% certain of the rule). 
In the second and subsequent turns, each player can either move an existing piece on the board or bring another piece onto the board as per turn 1.  

Different pieces move differently as follows:
-	Pawn moves one space in any direction 
-	Rook moves up to 3 spaces up or down, or one space to the side
-	Bishop moves up to 3 spaces around one of the rings, or one space up or down. 
-	King can move up to 3 spaces in any direction up or down

Once placed on the board a piece can enter the centre space or through it.

A player takes an opponent's piece by moving a piece into their opponent's piece's space.  Once a piece is removed from the board it cannot return.  I do not believe there is a rule to promote a pawn to a Bishop or Rook.

The King is the strongest piece on the board combining both the Rook's move (3 up or down) and the Bishop's move (3 around a ring in either direction). 

If the King is taken/mated the game is over.

Thank you Fergus, you spotted our problem right!

Thank you for pointing that out. I have now reviewed Pritchard's encyclopedia myself and agree there is a resemblance to Jabberwocky chess, but with fewer circles and no Queen (the King becoming the most powerful moving piece). I think we are getting closer to the origin story here of this board.

Arne Basse, from what I understand was a furniture designer, not known for chess boards. But he or whoever came up with this game could have been influenced by Parton. The timing would have been right as the board was produced in 1966. I wish there was a way to find out more about whether there is an archive of his designs somewhere, presumably in Denmark.

I like very much short-ranges games, even with not very strong pieces, and this game falls into this category. Here the piece set (only of max 2-square range) is logical and works well, and the presence of 4 Kings, of which one must be checkmated (with the consequence of a unstoppable fork on several Kings being a checkmate), is here to help the outcome of the game. However, even with the 4 Kings, the game seems to take a very long time to finish; the two games in this website that had been led to a conclusion took 85 and (for the game that ended with checkmate) more than 110 turns, which seems too much for a game of that type. And I am a little bit sceptical concerning the mating potential: when most pieces have been exchanged, the four Kings can more easily prevent the Pawns to promote.

One solution would have been stronger 2-square range pieces, in a game closer to a short-range version of Sac Chess, with a KNAD being the strongest piece (or at least Centaurs, or KADs). The presence of the KNAD, able to force checkmate without assistance, would obviously make the game faster and more decisive, but in the same time maybe less balanced and tactically interesting. (In Metamachy, the power of the KNAD/Lion is well balanced by powerful long-range pieces.) And I wouldn’t suggest a change in the piece set of this game; it works well as it is, and a like it.

Another idea is making a game with 2 moves per turn. With the same pieces and victory condition, not only this would make the game shorter, but also the attacks more dangerous and less easy to counter (and the possibility of double check with two pieces). This solution seems to me more interesting, while keeping the character and the concept of the game, than to have stronger pieces.

I think it usually makes more sense to have pawns promote only to pieces in their own army.

This looks like an amazing game! It combines shogi drops with a beautifully simple setup and set of pieces.

Reading the rules makes me want to play it; and also to design something similar, but it seems impossible to make anything quite as elegant as this.

Fergus, in Janggi, if I want to swap both pairs of horses and elephants with each other, do I have to do it in a single action?

Metamachy is fun. The historical pieces are all interesting to play with, and the fast pawns keep the game from slowing down too much.

Really? Insufficient material? What if the opponent has insufficient material?

Where can I find an editor so I can have a piece set uploaded?

This looks fun

Excellent write-up, Eric. I actually didn't know Fischer presented 960 in 1996 - always thought it has been around for longer.

This is a very good game. Everything fits together well. The random setup provides variety without being completely chaotic. The brouhaha squares are a great way to add more pieces without making the board so big it feels empty. The promotion rule encourages more variety in promotion, which is something I look for particularly; and I like the auxiliary pieces used here. The Mameluk especially is fun.

I think I might slightly prefer the Modern Apothecary game, for it's Dragon and Griffin, which to me are more interesting than the Chancellor and Archbishop, but I like the Siege Elephant and Mameluk as auxiliaries, so it's hard to choose one game over the other. I don't know if I'd agree with the statement that the Joker can't defend well. It seems to me that it's ability to mimic an attacker's move makes it particularly good at defending and more difficult to use aggressively. I'm not great at chess (in any form), though, so I could be wrong about that.

I'm interested to see what the next games in this series will be like!

The table in the center of this page has several mistakes in the description column