Ok, I think the image sever did'nt load all the pics I really couldn't see the bishop at c8, so I thought there was castle possible.

joshi tm: I thought there must be a rational explanation, just couldn't see what it was :)

Single elimination tournament. 1 win match. 7 days per move and standard vacation. Only rated players.
Eat, eat, eat! (Anti Chess)

In case Fencer wants to introduce yet another chess variant: chess-3

Can you give check with the king? Can you take your opponents king with your king? In normal chess, this is impossible, but in CCC, the first time a king moves, it moves as a queen, so it's possible to have a situation where one king has moved, and the other hasn't, threatening the other king.

The rules aren't clear about this; it's not mentioned in the differences with regular chess (that only mentions the king moving like a queen on his first turn), but such a situation is (obviously) not covered by the rules of regular chess.

AbigailII: No and no. The only difference between normal and cheshire cat chess (regarding king moves) is in the king's ability to make the first move as a queen. Only to make a move, nothing else. It still cannot move to an attacked square, cannot give a check, cannot capture opponent's king etc.

Fencer: Are you sure ? In that position : Échecs du Chat de Chester (mangue contre nabla) , my remembrance is that the system did not let me play e5xd4, which I interpreted as normal since the pawn was pinned by the enemy king (my king would be in check by the other king). But if what you say is true, e5xd4 would have been a perfectly valid move.

Or maybe my memory is at fault ?

nabla: I don't think you can move your king into check - and you can't move another piece that will in turn put your king in check - so if the system would have let you play e5xd4, then your king would have been in check (and then game over.)

If say your opponents king had already moved (so it is back to it's 1 space at a time mode), then letting your king (in it's queen move mode) check your opponent would have been acceptable.... as long as you don't put your king in danger.

Even though Fencer below says a king can't give check - I could have sworn that it can in this game while still in "queen-move-mode" against a "king-move-mode" king.

coan.net: Then our memories do agree. It would be worth to check which way the rules were implemented - and which way they should, which is not obvious. I'll see if the Encyclopedia of Chess Variants is more precise than the chessvariants.com entry.

Fencer: I don't think that regular chess rules actually forbid the king giving check - that would be a redundant rule: in regular chess, the only squares a king can ever attack are the squares directly surrounding it - but since it cannot be next to the opposing king (as it would threaten the square), it cannot give check.

But if giving check is not allowed, I would like to report a bug. In this game I played a move (6... d6) that emptied the diagonal between the kings, and it marked the move as "giving check". I do not know whether my opponent was forced to move his king - but he shouldn't if the king wasn't allowed to give check.

AbigailII: Ah, of course you are right, this kind of giving a check is allowed. What I meant was a situation when both kings (none of them made the first move) give a check each other - that would not be allowed.

Fencer: Fine then. The ECV doesn't give more details, but I like it the way the rules are.

Playing a game of Dice Chess at the moment has given me an idea for a new variation "Probability Chess" (better than dice chess I think).
Instead of a simple dice dictating which type of piece you can move, piece probabilities are calculated first, based on how many moves with each type of piece are possible.
For example, for white's first move there are 16 possible pawn moves, 4 knight moves but no others. Based on this Pawn is assigned 80% and Knight is assigned 20%. Then a randomiser determines which type of piece must be moved accordingly.
To illustrate this further, let's look at how a game might proceed. If white must move a Pawn and plays 1 e4, and then black must move a pawn and plays 1 .. c5, then white has 30 possibilities for the 2nd move: 15 pawn moves, 5 knight moves, 5 bishop moves, 4 queen moves and 1 king move. Based on this Pawn is assigned 50%, Knight 16.67%, Bishop 16.67%, Queen 13.33% and King 3.33%. White has a good chance now of being able to develop a piece, but if Pawn is chosen again then white should choose a move that takes into account how this will affect the probabilities of being able to move certain pieces next time. Later in the game you will be affecting your opponents piece probabilities too!
This is where a lot of the skill in this game will be, and what makes it more fascinating than Dice Chess.
Who thinks this sounds like a good game for BrainKing to support?

Beren the 32nd: A somewhat easier variant (easier in the sense of calculating probabilities) assigns probabilities based on number of pieces that can be moved. For instance, for the first move, 8 pawns and 2 knights can be moved, giving an 80% probability a pawn has to be moved, and a 20% chance of a knight. After 1 e5 c5, white can move 8 pawns, 2 knights, 1 bishop, 1 queen and 1 king, so he has to move a pawn with chance 61.5%, a knight with a 15.4% chance, and there's a 7.7% chance for each of the queen, king and bishop.

I've invented a new variant, I call it "Fencer random chess". It carries a certain element of luck. The game is played on a 8x8 chessboard, usual pieces, standard starting positions. moves are identical to regular chess, but capture is prohibited, so the number of pieces remains the same throughout the game. Since the captures are eliminated, the usual target which is the enemy king is no longer the object of the game.

So how is the game ended? simple: After each move, A Fencer random generator, at a probability to be determined, posts a message "white has won", "black has won" or, at a lower probability "draw".

The advantages of this variant should be obvious. The strategic calculations, which are so exhausting in the other variants of chess, are greatly reduced here. Anyone can easily master the techniques involved (OK, I have doubts about some members, but you can't have everything)

In my humble opinion, this game should become very popular on this site, in view of the quality of the other recent additions.

rabbitoid: What a brilliant idea, though I would have called it "Ludo Chess".

rabbitoid: ... and a further improvement could be the ability to have an "automove" setting which randomly selects a piece to move, then randomly moves it. then you would only need to look in your Message box to see if you won or lost!

How cool is that :)

WhisperzQ:
right, I totally missed that aspect :)

rabbitoid: A great idea. With your game, one will get the feeling of living without the tedious effort of thinking. I wonder whether WhisperzQ's suggestion wouldn't cut off some of the playing thrill though :-)

WhisperzQ: <sarcasm>Automove? Of course not. This being Brainking, you'll be forced to make your forced moves - after all, you might want to leave a message for your opponent.</sarcasm>;

Two ideas for Loop-chess variation:

1. A wonderful idea would be to prevent pawns in Loop-chess from promoting normally. Instead you can pick an opponents piece on the board. The picked piece, e. g. a rook, is removed and the pawn is promoted to a rook. The opponent gets a pawn in the hand.
This brings the tactical idea of removing opposing pieces by promotion, yet carries the disadvantage of not being able to choose pieces for promotion the opponent doesn't control on the board.

2. The second idea is to prevent checkmate by Drop!
That makes good tactics more essential for attacking.

Have fun discussing this or not!

Karthum:
1 is possible, but would make a new variant. What happens if the opponent has only a king left?

I doubt the utility of (2), the situation should arrive only very rarely. I don't think I've ever had the situation.

Karthum: 1 is interesting. I suppose that it would be allowed to pick a pinned piece (which makes a triple check possible).

2 is sometimes played but is widely disapproved by the community of Bughouse (= 4-players) and Crazyhouse (=Loop Chess) players as a beginner's rule. It does not enhance the tactics, just makes them more artificial - like instead of mating by dropping a line piece 1 away from the king, dropping a line piece 2 away from the king, the opp blocks, take the blocking piece with mate.

nabla:
1. Triple check is possible. Yet very rare in practice.

2. The rule gets very interesting in combination with rule 1. If you can only put your piece in play with a normal check, the opponent can take it off the board by promoting a pawn! :D
In my region bugchess is nearly always played with the combination of these two rulez!

rabbitoid:
If the opponent has only a king and pawns left, a promoted pawn is simply removed from the board!

Rule (2) comes often into play. Early checkmates with dropped pawns/bishops on f2/f7 can be prevented by blocking the own king. This is no beginners rule but quite an interesting defense possibility. Besides checkmating is often too easy by dropping a queen.

In knight relay chess can a king give check? If not, why not?

Okay, I see the kings aren't effected at all by knights. Why not??

ughaibu: it's explicit in the rules: "Any piece (except a king or a knight) which is guarded by a knight of the same colour..."

And by the way, the exception for the knight seems silly.

Good point about the knights, but why the exception for kings?

No idea there. As I see it, it would work just as well without an exception for kings. So kings could, for example give check - as long, of course, as the other king isn't protected by a knight. But since it's a rule change, it would be a separate variant.

ughaibu: Probably it is thought that because otherwise one of the knights would often be dedicated to the defensive task of enhancing the movement of its king, making the play less dynamic. But I didn't try it that way.

By the way, without the restriction about knights it might be unclear whether a knight connected with its colleague could capture a piece.

Why can't pawns promote in Recycle Chess?

Key McKinnis: Because the inventor thought it would be better this way, but he changed his mind since. I asked Fencer if he could restore the promotion, but he wasn't convinced (and he doesn't like rule changes). I have played Recycle Chess with promotions and I liked it much better that way.

Hi. I have a tournamet Chess - Elimination in All Variations II and in two days will be deleted. There is just couple games left but in some of them i need just one-two players so I would like to ask you to fill it up please. Thank you

Progressive chess is a highly popular variant in OTB play but few game sites seem to offer it. The basic idea is that the number of moves a player can make each turn increases by one each turn, i.e. white initially has 1 move, black has 2, then white has 3 etc. Putting the opponent in check immediately ends one's turn, even if you have further moves left. (There is a variant in which one can only give check on the last move of one's turn.) A player in check must relieve check on the first move of their turn or they are checkmated. I think this would be a great addition to the site.

agentofchaos: I agree, it would be a nice addition ...
agent, you are my opponent at Schemingmind playing Atomic960 tournament ...
Cheers.

agentofchaos: Yeah, Im a big fan of it. It's quick and easy. Was playing it with a friend of mine a couple weeks ago. It can produce some funny and interesting mating combonations.

ChessVariant:
Hi ChessVariant, small world eh! :-)
I'm pleased to see there's some support for progressive.
Cheers

I'm sure I've said this here before:  I'm a huge fan of progressive chess, and have had the chance to play some of the world's best.  If we were ever to add progressive as a variant here at BK, I'd love to see a Chess960 (fisherrandom) version available--possibly in addition to a variant that begins from the standard chess starting position.  It would make it possible for more original analysis.

From the standard starting position, progressive is a great variant for people completely new to it, or to those who are learning the tactics and mating patterns of conventional chess.  But specialists in progressive variants would probably appreciate the chance to break new ground from move 1.

wetware: I agree that Progressive 960 would be a good addition. Many variants could be played progressive - although I'd draw the line at Progressive Atomic! :-)

agentofchaos: Boom boom :)

Here's a thought...

Black's advantage is great, but White has plenty of chance to win, if he plays one of his Knights last, isn't it? Black should play nezt to that Knight that cannot drain points for played rooks...

joshi tm: I actually think it's the White who has some sort of advantage in Cheversi.

mangue: There is no automatic draw in chess, you have to claim a draw.

This is just wrong. If a position arose where no side can force a checkmate with any way, e.g because insufficient material occurred in the board, then it's an automatic draw no matter what. Even if one player loses on time it is still a draw. Such positions are called dead.

Imagine e.g a KNK position and the side with the single King to run out of time. Well it's still a draw.

there is almost no draw in dark chess, because you can never know if the 50 rules exist (how can you be sure your opponent did not move a pawn). So even after playing 500 moves, if your opponent still refuses to draw, you can do nothing.

But if you do not know if the opponent moved a pawn, you cannot claim a draw.

It is like the 3 times the same position. In dark chess, you often do not know what the opponent moved, so it is impossible to claim it.

Since in Dark Chess an arbiter is mandatory to exist to supervise the game and guarantee whether the rules are followed, it's easy to create a modification rule to the official Chess 50-move rule that could say, "If a position has arisen where no Pawn move and piece capture has taken place in the last 50 moves of both players, then game is a draw.".

No need for a player to ask about a draw.

Pedro Martínez: how come statistics says something different ?

What is the state space complexity and the game tree size for Cheversi? An approximation of course of the upper limit.

Constellation36: even if a player lose on time, it is still draw
Hmm, yes that's right, there is absolutely no point in continuing a game with KB against KB... but the draw is not "automatic" afaik...well, anyone trying to win with time with just a king should look for another game, maybe Tennis?

mangue:

Hi,

It's automatic. Most and in fact all arbiters would declare the draw, even if as i've said one player has lost on time.

ChessVariant: Cheversi did have different rules when it first came out - and was VERY unbalanced. (leading stats to lean one way) - the rule changed happened awhile back. I'm not sure exactly how the stats are once the rules were changed.

It would be interesting to know though. Not sure if that is something Fencer can look up or not.

coan.net: I think it didn't changed a lot .... for unexperienced players Black still has an advantage ... there is one or two tricks you have to discover to play well with White ... and this is the reason Pedro Martinez is talking about it ...