Comments/Ratings for a Single Item

This is an excellent game. I avoided it for a long time because I thought the large amount of power on the board would make it too difficult for me to deal with. It turns out I find it very playable, although it does require me to spend more time thinking before making a move for most of the game. Midgame positions can be exceptionally complex.

The opening starts out feeling nice and slow, as though the first 10 or so moves don’t matter too much. While I think it’s true that there is a very large amount of flexibility to how you can play the opening, those moves are still very important. At some point, typically around move 20, the game breaks open and becomes tactical and violent quickly. You want your pieces well-positioned when that happens. There is some contention for the e4/e9 and h4/h9 squares. All three of the light leapers – Champion, Wizard, and Knight – are good to develop early and all three are natural to develop to those squares, so you must choose which to develop there. I find that typically one of these three piece types doesn’t get developed in the opening before the game gets wild. I think it’s important to get the Vaos developed early. By the endgame, they are the weakest piece, but their low material value and ability to make long-range jumps gives them significant power to harass the heavier pieces as the game progresses. Developing the Vaos generally requires developing the Knights.

I like the promotion rules overall but the 14 extra pieces each player starts with in reserve seem unnecessary. There is tremendous carnage before any pawns are in a position to promote so lack of replacements is not an issue. The extra Queens are the only pieces that have any realistic possibility of being used.

Well-played games are typically nail-biters and the dynamic between the two players can reverse several times before it’s over. Having the momentum is very important – you want to be the one forcing the opponent to react, and the longer you can keep it that way, the more advantage you will accumulate.

My estimage of the piece values:

@ Greg

I'm curious how you estimate/calculate average mobility, if it's fairly simple to describe. I do this myself as one step when calculating my estimate for a knight's value on the (typically) rectangular or square board used for a given chess variant, by figuring out (and adding up) the number of squares a N can reach on an empty board from every single square, then calculating the average number of squares a N can reach on the board, if it were placed on each square one at a time. In Gross Chess, for example, there are a lot of squares from which a N can reach either 8 or 6 squares. Fwiw, I didn't bother to work out the exact average just yet, but estimated it must be around at least 6 squares (out of the impossible to reach 100% full mobility score, or 8, max.) for a N on an empty Gross Chess board. This seemingly isn't compatible with your 4.89 score for the N, but it does seem it could match your Average Directions Attacked figure for the N. [edit: your mobility score for a pawn in Gross Chess is a clue that you're somehow taking into account the average number/positioning of enemy and/or friendly forces on the board, too, though in that case I still don't quite get why the Vao and Cannon mobility fields are left empty in your posted table.]

[edit: Otherwise I'd note that I have a Cannon as 1/2 the value of a R (as it is in Chinese Chess), and similarly I have a Vao as 1/2 the value of a B. I'd also note that much earlier in this Gross Chess thread, Mr. Paulowich gave his own estimates for the piece values.]

There was an error with the Average Mobility numbers - I have now updated the table.

The Average Mobility is a Betza Mobility Calculation with a board occupancy of 30%. Basically, for a piece that can only make a single step, the number of directions attacked and average mobility will be the same (as though the board was empty.) For each additional step in a given direction, though, the weight is that of the previous step multiplied by 0.7 (to approximate a 30% chance that the previous square was occupied.)

About promotion from my experience with the two apothecary games which I have designed and I had the promotion rules similar (although at the time I have forgotten the exact game from where I had took the inspiration) most often the rook is the piece of choice because on rare ocasions the extra move actually worth it. HG pointed that first to me and I tend to agree. But it is much more fuzzy probably than him and me actually though about it initially. Probably here is the same thing. But for promotion extra on the side material 1 queen, 1 rook and 1 knigh would be more than enough.

Hello Fergus,

In the preset for Gross chess this line of code appears:

elseif and not fnmatch "*;*" thismove == P space #to:

It appears in the pawn promotion subroutine. Could you explain in a few words what it does, as I can't get my head arround it?

Thanks!

It checks if a Pawn is on the destination space and if only one move has been made on the present turn. If these conditions are met, it tries to complete the move by asking what to promote the Pawn to.

Thanks, Fergus!

I found a bug in the Gross Chess preset.

It seems you had forgotten to decrease the number of pieces in reserve once a piece was promoted to. You may reproduce the bug following the below steps:

1. arrange the capture of wizards 

2. Use a pawn to promote to wizard

3. Use again a pawn to promote to the same wizard

I don't think that is what you intended.

I'll bear that in mind while working on a new preset for Grand Chess. With that as a foundation, I can start on a new and improved preset for Gross Chess.

Have you any ideea Fergus, at first glance what would be the correct instruction to decrease the value of the just pormoted, in the RESERVE array?

Test comment to see what email notifications look like.

I suppose it is not going to notify me of comments from my own account. Let's try this again.

I have noticed that several games of Gross Chess end up with some Marshalls and/or Archbishops unmoved. Maybe the presence of two Marshalls and two Archbishops is somewhat excessive. I wonder if a variant with a single Marshall on g1 and Archbishop on f1 with empty a1, b1, k1, l1 would be worth to be investigated.

I think the archbishop(s) is better on the side. That eases it's development.

Hmm, this is not obvious at all. Archbishops are very mobile and develop easily anywhere and in this respect the center of the back rank is not less favourable than the sides. I even think they can develop easier from g1 because the center Pawns are often moved first, freeing their squares, than from b1, k1 where they are trapped.

I think Aurelian may have meant he would prefer if the Archbishops were each one square in front of all the Chancellors. However, if they developed two squares forward like a Kt, they might be vulnerable to an undeveloped enemy Vao.

Having the Archbishops in the centre on the 1st rank would seem to be a possible improvement on the setup too, but I think Fergus may have definitely wanted the Cannons of an army to have empty squares to move to (on the 1st rank) at once, if a player desired, sort of like in (10x10) Shako.

Jean-Louis understood what I wanted to say, well. Thanks for the interest Kevin!

Thanks Kevin and Aurelian. I understand. Placing the Vaos needs care indeed, I met this also in my variants. I concluded that it is best to put them in the center of the 1st rank as much as possible, at least not on the sides, to avoid that they threat the opponent's lines too early, as soon as the center Pawns are developed.

In the case of a single BN and single RN, then maybe the full 1st rank would have to be considered in order to give the Cannons a max of lateral mobility and a avoid a premature threat from the Vaos. Interesting.

There is also the issue as having all pawns protected in the initial position. Don't forget about it. Although with so many pieces this is relatively easy to do!

An experiment might be to switch all the Kts with the Champions AND switch all the Wizards with the Archbishops, in the setup - play testing could proceed from there, if anyone thinks this may be a good idea to try.

The reasoning is that not only may the Archbishops get into play easier sooner, but the development of the Kts and Wizards will not take away nice squares from each other (nor the Champions from the Wizards). A drawback is that the Kts are farther from the centre, but in Fergus' setup that tries to please Kt fans it's the Champions that have to suffer that instead (and squares they want to develop to are ones both the Wizards AND Kts may want to, too). However, another drawback would be Wizrds have less nice squares to develop to. [edit: yet another drawback would be that a Wizard could no longer develop to attack an enemy centre pawn that was moved by a triple step]

My initial question was about having 2 BN and 2 RN. I was thinking in a setup with only 1 of each.

An experiment might be to switch all the Kts with the Champions AND switch all the Wizards with the Archbishops, in the setup - play testing could proceed from there, if anyone thinks this may be a good idea to try.

One of the deliberate features of the setup is that every piece except the Vaos has an empty space it can move to behind the Pawn line. If you made these changes to the setup, the Knights, Champions, and Archbishops would no longer have any empty spaces they could move to behind the Pawn line.

I have noticed that several games of Gross Chess end up with some Marshalls and/or Archbishops unmoved. Maybe the presence of two Marshalls and two Archbishops is somewhat excessive.

Even if a piece doesn't move, it influences the moves of other pieces by protecting or threatening other spaces on the board. So, not moving these pieces isn't evidence that they are playing no role in the game. This may rather be a sign that because of differences in playing ability, one player is having an easy time defeating another player. In the endgames I can recall from Gross Chess, both players got down to very little material and had to employ whatever pieces they had left.

I wonder if a variant with a single Marshall on g1 and Archbishop on f1 with empty a1, b1, k1, l1 would be worth to be investigated.

One problem with this is that it destroys the symmetry of the setup. Another problem is that it leaves the King, Queen, Bishops and Cannons without any empty spaces to move to behind the Pawn line, and a game with this setup may as well be played on a 10x10 board, since it doesn't make effective use of the greater space provided on a 12x12 board.

What might a concrete advantage of every piece (except Vaos) being able to move behind the pawn line in the setup be? [edit: closest thing to that I can think of, so far, is that a player sometimes just might be able to evade an attack/skewer by an enemy Vao or Cannon, in a way he couldn't otherwise]