Comments by benr

I would play some 3+ dimensional variants.  As Joe might be able to confirm
by now, my chess playing skills might be a bit lacking, but I think I can
hold my own at design discussions.

Dan Troyka includes an impressive history on high dimensional variants in
his 6D chess download.

I have proposed an (countably)infinite-dimensional chess game before, but
the complete lack of visual ability dampens hope for ever actually playing.
 :P

Unless anyone minds, I might collect and edit some ideas from here into the
wikidot.  It would be nice to have a relatively central source for these
things.

Daniil:
I'm not certain, but I don't believe there's a nice tiling of 3-space which is hexagonal in all (reasonable) directions.  Maybe you can manage it, but only by thinking of the cells as points to occupy rather than regular, spacial objects.

Daniil, are you suggesting a different game?  In this game it seems that compound pieces (including the two variant pieces) never promote, and only demote upon capturing.  Any noncapturing move they make leaves them as they are.

It is interesting that a queen can never demote then promote back to a queen, whereas the variant pieces can demote then promote back to themselves.

I really like this concept, though I haven't played it before.  Concerning the sample 'Case II', it is worth noting that even if U captures R--freeing B--W can immediately recapture B by the same move suggested.  (It might be worthwhile to capture B now (as in the suggestion) just to threaten U's current square (if R is ever captured at his starting square, that is).

Rooks do have the devastating ability to win the game in four moves (after two moves getting into position) by sweeping through the opponent's home row if they can avoid being captured first.  While bishops enjoy greater mobility, their range is only half the board, so I think the pieces are relatively well balanced.

So this is really (locally) a hexagonal game, since each 'square' has six neighbors; is it different (globally) from a standard hex setup?

EDIT: Ah, I missed this discussion a couple years back.  I think perhaps the original comment by Gilman answers my question most fully: it's not a 'standard' hex setup.  It seems too that the piece movement is not standard for hex games, but I don't see anything that forces us to use the pentagonal layout for ease of visualization.  It is neat though how the pentagons have been laid out.

When playing on borders, how do you define an adjacent location?  Is it a
border that shares an endpoint with the current one?  I suspect a lot of
these ideas will wrap around onto one another (for instance, the duality
between triangular and hexagonal boards, the self-duality of rectangular
boards, etc.)  I think also that when you pass between these viewpoints,
some of the pieces may be defined differently from their standard.  (That
is, if you define what you think pieces should do in a hex corner game,
perhaps they will move differently than what their counterparts in
triangular chess usually do.)  This may or may not be a good thing.  I
generally like it, but it's nice too if they work out to be consistent.

Another way to get triangular is by playing on the corners of a hex grid, so you could use the rectahex board in the same fashion; you just have to be able to remember that the intersections of a vertical edge with what appears to be a square's edge is actually another corner (since the apparent edge of the square is in fact two separate edges in the rectahex sense).

Looking a bit more closely though, this won't work if the board is turned around in the 'proper' orientation.  Notice that the corner of the hexes d4,d5,e4 should be adjacent to the corner of the hexes d5,e4,e5; but on the usual orientation these are the same corner!  You could get around this I suppose, but it would be ugly.

I think everyone should keep in mind the line below the game:
'These are simple illustrations rather than strong opponents.'

The beauty of this applet is Ed's extension of it to so many variants.

George, I don't understand your calculation.  Each non-king piece starts with 7C, so there are at least 30*7=210 non-king moves that can be made.  And each capture increases this number, right?

Also, the wording is a bit ambiguous regarding captures: the captor recieves 'Calories equal to its traditional value'.  I read that as the value of the captured piece, is that correct?  [E.g. if a pawn with 4C captures a knight with 5C, then the pawn now has
4 - 1(movement) + 5(knight's Cals) + 3(bonus) = 11C ?]

Also, I presume that a pawn retains its Calories upon promotion?

I have to largely agree with the direction of that article.  It should give
some overview of the idea behind 3D chess, and list some few noteworthy
examples.  Then, I think the link to this site is sufficient as an external
link for other variants.  I would emphasize the multitude of other existing
games in the article and reference the external link, but I think listing
too many examples directly in the wiki article may be too much.

I think your image of the contraction capture is off...also I'm not sure I understand the Drop rule.  Can you get the queen before placing the remaining four pawns?  Are captured pieces droppable?

The Big Crunch idea seems to already be in place in terms of the contraction of the board.  An interesting implementation of the Big Rip idea would be to have the board disappear from the inside out rather than contracting:  say the outer edge of the board is determined by the number of pieces placed throughout the game, and the inner edge is determined by the number of captured pieces.  (This assumes captured pieces are dead for good, not switching sides and dropped.  Also, this probably isn't very close to the actual idea of the Big Rip.)

Not to spark another debate on what constitutes a chess variant, but I imagine this fails the criteria for most people.  Gameplay is nothing like chess, but uses chess equipment.  (This is not to say it doesn't belong here, I think CV.org should be fairly all-inclusive of anything chess related.)

As to MP's proposed alternate puzzle solution, it assumes that the ball may be kicked 'past' an allied piece.  This seems to be disallowed by the rules, but not specifically.  If we think of chess, such a move should be disallowed; if we think of soccer it should be allowed.  Also, the rules disallow passing to an unmoved piece which doesn't follow soccer very closely.  (I would propose each piece be allowed a null move, that would include the possibility of passing to a friendly piece provided it makes the next (null) move and kick.)

Note too the applets
/play/erf/SoccerC1.html
/play/erf/SoccerC2.html
(interestingly, Ed doesn't have a link on his personal page to SoccerC2; finding it here was my first clue to its existence!)

See also 'Joust', described here
http://www.chessvariants.org/programs.dir/joust.html
and with Friedlander applet here
/play/erf/Joust.html

(In Joust, the question as to whether the knights can capture one another is interesting.  If yes, only one player has this option and thus an advantage (?); but if no, one player has an additional blocking ability that the other does not.)

Joust is interesting from a mathematical combinatorial game theory perspective, as it should be solvable with enough thought/force.  Knight Chase introduces an extra element of droppable markers and a time limit, which should make mathematical statements more difficult.

First, if in the position the white builder were at d4 instead, then that rook move would remove the check, right?

I agree tha the builder is too strong; at least for a start it would make sense to disallow the builder trying to swap out the king.  (After all, you could never successfully switch them!)  It would still have the awesome power of resurrecting your pieces, plus capture by adjacency, but no direct checking power.

I really like the idea here.  It looks like there are 20 types of cards, 5
of each type.  Each game takes two types for the starting decks, another 4
types for the basic set (in every game), and another 10 types in addition. 
This means each game uses 10 out of 14 possible 'extension' cards.  I
feel like it would be better to have a greater variety of cards available
(as in say Dominion) for more randomness and replayability.

Anyway, I'll probably end up buying the game regardless.  Maybe expansion
sets are in order?

Yes, the rules need to be clarified a bit.  It sounds though like each
piece moves as usual within each level, and steps to a corresponding square
in either of the adjacent levels (excepting pawns, which could only move in
one direction).

I'm happy to chat about the game, but I warn you that I tend to really
prefer games that treat the third (or fourth) dimension equally to the
first two.  Also, I'm in Illinois, so it will have to be restricted to
internet correspondence.

Your king restriction rule reminds me of the one in Joe's 4D game, but
with a twist.  Intriguing.

I also enjoy the historical notes.  I would be very interested to hear
about something noteworthy happening 500 years ago.  I don't think these
notes need to be generated every day, but every now and then is nice.

The knight here has of course just two moves in its lifetime.  Dropping a knight becomes a tricky subject (although I suppose in my few Shogi games I rarely want to drop a knight).

I assume the proposed promotion zone is the last hyperrank?

I think I would suggest different diagonal movement in this game.  As many of the Shogi pieces see 'forward' differently than 'sideways', it is perhaps better to keep track of the two 'forwards' and the two 'sideways' directions in this 4D board.  In particular, I think the moves from center square Bb2ii should probably not include Bb3iii, nor any of the extended diagonal forward&back like Bb1iii.

I also think that there's a possibility that king restriction (beyond eliminating tri- and quad-ragonals) is unnecessary.  This board is so compact that the dense moves of the generals, the enemy king, and especially an enemy dragon king or dragon horse could force mate.  (In fact, if 3- and 4-diagonals were included, a dragon on the center square sees everywhere.)

(And Charles, Daniil's sentence is fine with the omission of those commas and replacing 'which' by 'that' (a grammatical technicality not recognized by most).  I think such cells will occur infrequently enough to not warrant a universal name; one needs a particularly asymmetric piece to have any such squares.)

The main distraction for me as far as layout is the bulleting.  Using html bulleting would be considerably more readable.  Also the headers would be a bit nicer in the cv standard format, and I agree that the long spaces after diagrams is irksome; I don't know why a red line would come about when deleting that space...

I haven't really read through the entire thing, but I find the snippets I have read to be fine text-wise.  (I understand renaming standard pieces for thematic/historical purposes; however, I too find it harder to read the result.)

I was reading over the Tetrahedral Chess page a while back, and decided to
understand the statement that certain (skew) planes form hexagonal
chessboards.  I can confirm now that this is true, and Gilman's M&B even
enumerates the number of such planes through each cell.

Now note that the 4-coloring of Tetrahedral Chess lends all four of its
colors to these hex-boards.  I cannot recall finding a hex chess that uses
a four-colored board.

However, a longer period of time ago, I noticed that the hex board can be
thought of as a certain quotient (that's a technical math term in this
context) of a 3d cubic board along a single unicorn line.  (For those not
used to the math lingo, think of it as an optical illusion: you look at the
cubic board so as to line up opposite corners, and all cells along your
line of sight are treated as being equivalent.)  This quotienting does some
weird things with the pieces, but what about the colors?  The only obvious
coloring that could be maintained by this quotient is the unicorn's
4-binding!  It probably comes as no shock that this coloring is the same as
in Tetrahedral Chess (how many 4-colorings can there be of a hex board?)

I think furthermore that some of the pieces in Tetrahedral chess, when
restricted to one of the hex-planes, turn out to be very similar to the
cubic pieces modulo the unicorn's diagonal.  (I had worked some of this
out, but don't have the notes handy.)

I agree that we should look for a continuum; probably the best approach is to decide upon several factors (like the Muller 7) that can be reasonably easily computed for different games.  What is perhaps lacking from the Muller7 is a measure for which aspects are most important (perhaps it is just equally weighted, but I think they should not be).  The ultimate goal (IMO) is for the measurements to come as close as possible to our collective opinion of what is 'chesslike'.  (See also Joyce's 'Chess Space', on the wikidot as well as in some comments here I believe.)

A couple of examples that might be helpful to keep in mind:
1) games using chess pieces that are not chesslike in gameplay: Joust (not very chesslike), or Knightsweeper (not chesslike at all) [both on this site]
2) Lennert's 'For the Crown' (half chess, half something else)
3) already mentioned, but Go and Checkers (and their variants; Gess perhaps?)
4) other games that are clearly not 'chesslike' but that have similarities should be noted; these might help weight the characteristics.

If 'chesslike' is not well defined enough, maybe it's useful to think in the following way.  If you wanted to tell a friend about this game, is it easier to say 'It's like chess, but...' or just to start from another game (or from nothing at all)?  Of course, some games will be equally easy to start from chess or to start from some other game (e.g., For the Crown seems easier to describe as 'like Dominion, but with chess', but maybe for some people, 'like chess, but with deck building' is better).

Oh, and maybe it's good to distinguish between a theoretical classification and guidelines for this site.  I tend to think this site should be very inclusive, but am happy to draw the boundaries tighter in theoretical talks.

Not sure if this really belongs as a comment on this page, but here goes.
Raumshach is a bit like a diagonal game, but in higher dimensions diagonal starts to have different meanings (the colloquial 'triagonal', etc.)  I've taken to giving the number of dimensions that are 'lateral' versus those that are 'attacking'.  So Raumschach is 1-lateral and 2-attacking.  Some of the very large 3D (8x8x8) variants are 2-lateral and 1-attacking.  Most 4D variants are 2-lat and 2-att.  Ordinary chess is 1-lat and 1-att, whereas Diagonal chess is 0-lat and 2-att.

I generally like the idea.  I think the inventor shouldn't rate the game;
if they want to mention what they think of the game, it should go into the
page somewhere (in the introduction would be good).  I'm a little worried
about rating games when they are themed or experimental: for instance, my
only game is 4D, so probably not a good candidate for frequent play, but
(IMO of course) it is a very good setup as far as 4D games go.  Should it
get rated in the former sense or the latter?  Maybe the frequency of play
question will serve this purpose too, but maybe there should be a third
rating?  (So 'good game', 'interesting', and 'often played'?)

I like the text itself.  It's formatted to take up less than half of my
screen's width though, and I prefer the current page's full span.

Maybe this is premature, but I have some comments for the login box.  It
would be nice if it said something if you fail to log in; I think right now
it just refreshes the page without any message.  It might also be useful to
have a link to register for the pages in the same box.

This exchange makes me wonder how hard it would be to create an applet that allows one to choose a small grid and fill in certain locations with flags, then outputs a list of named pieces (with links to appropriate CV pages) that share those moves on that grid (or perhaps--as options--at most those moves or at least those moves).

It seems that most of you already know this, but maybe it's still helpful
to note that there is a definite answer for who wins chess given perfect
play on both sides (white, black, or neither [draw]).  This is true of any
chess variant that involves a fixed turn structure, perfect information
(& no randomization), and finite length (here's where we need something
like the 50 turn rule).

So, in the mathematical sense, any such chess variant either has a perfect
1st turn, perfect 2nd turn, or absolutely no advantage.

Joe keeps referring to "noise", which is how we can manage to talk about
a 1st turn advantage without the mathematics making it boring.  So far no
one has actually defined the framework of the question, but it seems
generally to be accepted as referring to people's current thoughts on
optimum strategies, and how those interact.  I suppose to make this
rigorous we would want to define the fuzzy value of positions (it's
unclear how to do this, though current chess programs are probably a good
starting idea), then allow for some randomness in the players' moves that
biases toward high value positions.  Then I think we should say there's
"no" advantage if the probability distribution of wins-draws-losses given
this framework has no advantage with statistical significance.  So we say
there's no advantage if the noise drowns out whatever perfect mathematical
advantage actually exists.  (I think this is essentially what Joe has been
saying?)

Rodrigo, I think the idea is that if after white's move, black's only response will put white in (non-mate) check, then that black move is illegal, so black is in fact in checkmate, and white's move was legal.

Then, what happens if black's only response is to put white in a similar position?  This is the "paradox" that is referenced.

I agree that this is really neat.  Perhaps the 2007 comment makes it clear that this page should state more clearly at the beginning that this is a form of chess problem, not a suggested new method of notation.  :)

In fact, since I now see the "problem" icon attached to this page (but couldn't until I looked at the comments or re-found the page through search), maybe it would be beneficial to head every page with a note about what type of article it is?

It seems that you want the diagonal moves to be either diagonal within a layer, or triagonal (in the sense that Malcolm described).  Is that a fair assessment?

Do your kings also move this way (orthogonal or "special diagonals"), or do they really get 26 directions?

Do knights leap, or slide?  If they leap, you needn't say that they can go 1 then 2 or 2 then 1: they are equivalent.  (Saying it isn't bad, but it makes me think perhaps they don't leap...)

I agree that the checkmate example probably isn't checkmate.  That should get fixed/clarified.

The queen "holding" rule is nice, and a bit reminiscent of a rule Joe Joyce used for a 4D game.  However, it then seems likely that minimum mating material is FIDE chess mating material plus one queen.  Practically requiring a queen for mate seems like perhaps you should include additional pawns.  Or maybe a different piece should have the holding ability?

Namik Zade, you have three submissions for Knights games; did you mean to
submit all of these?  I tried to contact you via the email address listed
in your account, but the message bounced.

(In reference to Jeremy's note about comment display weirdness:
It occurred when the associated page was deleted; the hanging comment is handled strangely.  If an editor who knows more about the php code can fix this for the future that would be nice; for now I've just moved the comments for the deleted sovereign chess page into a non-page comment thread.)

I've added the pending submission link into the new menu.

I'm not getting anything coming up when I go to the Change Password page
via my membership info page.  Has this happened to anyone else?  Fergus, do
you know what's going on?

test comment: made after isDeleted was set.

It seems this entire book is now available as a free eBook.

http://books.google.com/books?id=XbbhY4Q6U0IC

I don't read German, but it looks like the book is entirely about the 8x8x8 version.  (There's some mention of different sizes, but I don't see any mention of a 5x5x5.)  Interestingly, the pieces are set up on the first two levels (instead of opposite levels as the 5x5x5).

Of course, there are some variants on these pages played on infinite
boards.  I have thought a bit about infinite-dimensional games as well.

I suppose any large size is workable, especially if pieces have short
moves: the game becomes a large map, which you could zoom in on a sector of
and make relatively normal-looking moves.  (It becomes a discrete version
of many RTS games.)  Infinite-dimensional doesn't admit as good a visual
tool.  :P

I believe I have the RSS feed working again.  Let us know if anything goes wrong.

As for the no-trading rule, see also Angel Chess (Ed has a java app for
it).

Thanks, after I got it working in Yahoo and Google I didn't actually run it through a validator.  Error-free now.

The new header includes a link to the signin/join page.

I could delete your old account Daniel, but it would be nice if we could find out what's happening with your temp password, to prevent future problems.

I'm not really sure if this qualifies as a 4D variant, but I've indexed it that way to be as inclusive as possible.

If pieces couldn't turn at the knot, I would insist that it is 4D, but which is easier to explain here: four disjoint 1D boards with a glued square, or a subset of the 4D board with turning pieces?  (Note that in the 4D interpretation, the Entity's teleport power is almost the same as a 4D bishop's move.)

I'm not sure how practical an offline app would be.

I agree a random article would be nice, but I'm not sure exactly how to implement it, especially since our articles come in two flavors: hardcoded html and database entries.  And should it just be game articles?

This is especially useful for finding variants in the intersection of various categories.  For instance, to find 3D variants where there is some kind of hexagonal component (hex prism or tetrahedral e.g.), set up the search just for 3D variants, then modify the resulting URL so that it includes "category=3D,hexagonal".

Why is capitalization mandatory?  What is the "far right corner"?  Should the heart get up to 6 steps to complete the image?  (Isn't the fifth step downward?)

The rules for how/when buildings are built/destroyed, units produced, and amenities produced seem unclear to me.  I think a sample game opening would help a lot.

Are pieces set up initially centered along a board edge?  Some of these pieces probably deserve a diagram to help see what's going on.

It seems also that the webmaster of the pages has kept a copy:

http://didymus7.com/nost/index.html

4+ dimensional chess variants have their own category here (is it the only one small enough still to fit on one search result page?). I'm not sure what you mean by the 4d games here being "stretched 3d".

Here are my personal opinions on some of our 4d games:
Chesseract: pure 4d, some strange pieces
Timeline: not very chesslike, but pure 4d geometry
Hyperchess, Walkers&Jumpers, Sphinx Chess: 'mixed' (2+2)d geometries
Fabulous Flying Kittens: I still don't understand how this works
TessChess: my own, perhaps too pure and therefore subject to analysis paralysis

See also the sister wikidot
http://chessvariants.wikidot.com/start
http://chessvariants.wikidot.com/3d-design
for some other (non-game-specific) (3+)d comments.

See the Developer Guide:
/play/pbm/devguide.html
in particular the section called Editing a Preset.

I'm not sure if one can get a clean slate preset; it's best to find a game somewhat similar to yours and edit that preset into one for your game. It's fairly easy to get a preset setup to play most games, but getting the preset to check rules can be more difficult; most presets available here don't check rules (as far as I know).

Greg: from the log page, go under the header Related, This Preset for...
Or, the Menu button to the right of the log block.

Joe: I notice that in the logs you appear as both white and black.  Is this
just when I view it?  It doesn't look that way for other logs I view. 
Maybe something is wrong with the multiple moves...?

It sounds like perhaps you're misunderstanding the rules. Each turn a player attempts to make a move as usual. If the opponent wishes, they can force the player to retract that move and make another.

What you describe sounds like No-Chess
http://www.chessvariants.org/other.dir/no.html
For that game, I think the answer to your question should be "yes". In particular, white can "refuse" some impossible move.

When I had looked at it this morning the html tags weren't around.  I've
fixed the offending closing tags.  I think I should leave it to Freederick
to fix up other formatting issues.

I've hidden this page until some things are cleaned up.

I have finally found out how submissions were coming to be attached to your name Freederick.  I believe I have fixed the underlying issue.  For the submissions with your name incorrectly attributed, I have changed the author to me for lack of better option (I don't think we should just delete the items).

I have changed the author to me for lack of better option.  (I don't think we should just delete the items, and I don't think there's a way to discover the actual author.)

Mariano, I've sent you an email concerning this page.  I have also edited your comment for language.

Sorry, in fixing the bug mentioned earlier I broke this; I believe I have
corrected that error now.

I don't understand the difference between your two statements.  What
exactly do you conjecture to be true?  Why does 49 not give a
counterexample?

I'll look into it, but I'm not too familiar with Game Courier yet.  Send any important details to the general contact email and/or Fergus.