Read the text and the examples. You will find that they are really simple and pretty.
Circe
One of the most popular conditions of the fairy chess is Circe. In its initial form, was described by P. Monreal and J. P. Boyer in 1968. Since then, Circe and its many variations, have often offered pleasant moments to the friends of the chess compositions. (See here, here and here).What is the peculiarity of Circe?
Let us forget the way we capture a piece when playing Over-The-Board chess, because if Circe is active, the captured piece will not find easily its way into the box of the chess pieces. In any capture (King excluded) the captured piece will be reborn on its "initial" square. If that rebirth square is occupied, only then the capture is final and the captured piece is removed from the chessboard.
How the rebirth-square is specified?
For Queens and Bishops there no difficulty - their initial square is unique. For the other pieces, it is specified by the color of the square where the capture has taken place if the captured was Rook or Knight, or by the column where the capture has taken place if the captured was Pawn (or fairy chesspiece). For example, a black Rook captured on a7 is reborn on h8 (since it has been captured on a black square) while if it was captured on c2 the rebirth would happen on a8. If we capture a white Pawn on d6 then it will be reborn on d2.
It is important to remember that castling with a reborn Rook is allowed.
It is crucial to observe that the move is not considered finished when we put the capturing piece on the board, but when all the Circe-effects are completed.
Detail : Since we consider that fairy pieces have originated by promoted pawns, their rebirth-square is the promotion-square of the file where the capture took place. If we capture a white Grasshopper on a4, it is reborn on a8.
Circe does not allow us to capture of a piece, when the reborn piece checks our King.
We note a Circe-rebirth inside square brackets. The symbols that annotate a move (like ! ? + e.p.), are written after the brackets. For example, if a white Knight captures the black Queen on h1, we do not write simply 1.Sxh1 but we append the rebirth (plus a black Queen on d8) in brackets : 1.Sxh1 [+bQd8] .
If a Pawn from g7 captures the bQh8 and then is promoted to a Rook that gives check, the move is written more complicated : 1.gxh8=R [+bQd8] + .
Example of self-protection
One of the effects that diversify Circe from the usual chess, is that the pieces have sometimes the ability to protect themselves. Remember that the moves are not completed when we put the capturing piece on a square. We must first examine the possibility of the captured piece to be reborn somewhere on the board and then we can characterize our move as being legal, giving check or mate, or defending. For example, the most usual Circe-mate is probably the following :
 | Position 472_01 Let us suppose that the white Queen was on g1 and played 1.Qg4+ |
The first reaction on usual chess would be 1...Kxg4 where the black has the unique move to capture the unprotected Queen and then it is safe. Wrong! Since black has captured a white piece, we must examine what happens if it is reborn. The square d1 is free, and thus the white Queen is still in the game! It is reborn on d1. So, if the bK captures the wQg4, we will have the following situation :
 | Position 472_02 The black King exposes itself to check! That means, it can not capture the wQ on g4, and thus the white move was giving mate 1.Qg4# |
Allumwandlung (AUW)
Having the ability of "self-protection" on mind, we can use less material to a mate formation. And talking about "less material", why do not we use a Pawn that would be promoted to a piece? And furthermore, the defences of the black could come from promoted pieces also! The idea is substantiated in AUW form, that is, we will try to make the 4 possible promotions in the variations of the composition.
But how, exactly, can this happen? In all probability White should queen a Pawn in one variation and promote it to Rook in another. In a different situation it would be difficult for us to form a mating net since we do not wish to load the position with many pieces. We also choose to compose a helpmate in two moves.
Should we see what happens with a wP in the seventh row? With the W1 (=first white move) it is promoted and with the W2 it delivers mate. This sounds simple! If the promoted piece is a Queen, it could be nice to be on d-file when checkmates, in order to be self-protected. Well, let us promote this wPd7 to Queen on d8. The checkmate can be delevired from squares d2 thru d7. (Not from d1 because, if wQd1 is captured on d1, the rebirth square would be occupied! Not a big nuisance, though...)
A wRd1, if captured there, can be reborn on h1 and can control a1-g1 from there. That is good! But how can we block squares around the black King? Let us suppose it stands on e1. A bKe1 can be threatened from a wQd2 or from a wRd1. We will need a black Pawn on the 2nd row, which will be promoted with move B1 to Knight or Bishop (in order for us to achieve the AUW theme) and with move B2 will block a flight-square.
 | Position 472_03 |
With the queen on d2, the square f1 must be blocked with a black piece, and if this piece is promoted only bQ or bR can reach f1 in one move... (so forget the AUW).
Should we threaten mate with a rook on d1? We need to block two squares :
 | Position 472_04 |
On e2 can stand a bishop and a knight on f2. We prefer this formation since they can capture on d1, but Circe will send the rook to h1 with check, so the capture is not a legal defence. As we see it we need two black pawns. One to be promoted and one on e2 or f2 to watch patiently the action...
With a little counting, we see that promotion to a black bishop and placing it on e2 in two moves is no good. That is, with a pawn on f2, only a pawn on d2 can be helpful :
 | Position 472_05 1.d1=B d8=R 2.Be2 Rd1# |
But things are now very tight for one, uniquely defined, mate by the queen in the other variation.
Let us try to leave a pawn on e2 but block f2 with a knight. The promotion must take place on file-d or on file-h. If we try with a bPd2, the pawn on e2 closes lines in the other variation where we promote on d1 to bishop, which would be extremely difficult to get near the action. So we start with a promotion on h1 and if need arises, we will think of something different...
 | Position 472_06 1.h1=S d8=R 2.Sf2 Rd1# since Circe does not allow capturing of the rook by Black! |
Splendid, we have a working variation. And we know that in the other variation we must promote to wQ and bB. The queen will check from file-d. Since d1 and d2 are not suitable, let us try a little higher. This means that the black king must be relocated. Moving it towards the "interior" of the chessboard, more flights must be controlled by the White. Again, the black pawns must help for the formation of the mating net. Let us place the black king on e3...
 | Position 472_07 There is a nice picture of mate... all it needs is to bring the white queen on d4! |
Satisfaction! It seems we have succeeded. And we must not forget to leave the white king somewhere on the chessboard! But ... on f3 can equally well go a black queen, yes? The mate is still valid.
 | Position 472_08 |
Well, this can give an active role to the white king! wK must not allow 1.h1=Q. So, we place it on h7 :
 | Position 472_09 Ready! h#2, 1.h1=S d8=R 2.Sf2 Rd1# |
 | Position 472_10 and twin : bKe1->e3 (bK must be relocated from e1 to e3) 1.h1=B d8=Q 2.Bf3 Qd4# |
Our compliments to mr Klaus Wenda, who in 1985 was awarded 2nd recommendation from feenschach magazine with this problem (WinChloe 245497). (The difference is in the position of the white king, where the composer does not allow the promotion of bPh2 to queen, by not allowing to it to step on f3. The solutions, as the reader can easily certify, are identical.)
 | Position 472_11 Klaus Wenda, Feenschach 1985, 2nd commendation h#2, Circe, twin : bK->e3 |
We can easily find similar examples in the problem databases, as the following (WinChloe 123172)
 | Position 472_12 Per Bjørn Grevlund, Stella Polaris 1973 h#2 Duplex, Circe 1.g1=B d8=R 2.Bf2 Rd1# (Black plays first, White wins in 2) 1.d8=S g1=Q 2.Se6 Qg5# (White plays first, Black wins in 2). |
Note : The white pawn on h5 stops undesirable effects, as 1.Kg5 g1=Q+ 2.Kh5 Qg5# (bQ is self-protected because its rebirth square is d8).
Pictures of Mate with Circe condition
We saw that things are a little different when Circe desides to haunt our chessboard. Which are really the pictures that will allow us to mate the adversary King, those Circe-specific pictures that do not appear in an ordinary OTB game?
Let us start with something simple. A white Queen on the firts line, alone and unprotected by other white pieces, can achieve a valid mate, because the black King can not capture the wQ since it is reborn on d1 and checks the bK from there. That means the move of the bK exposes it to check! Thus the move does not agree with the laws of chess.
 | Position 472_13 |
Something more interesting is shown in the next picture, where the bK seems to be relatively safe. Or is it?
 | Position 472_14 1.Rxh7 [+bSg8]# |
The Knight was captured on a white square, thus it is reborn on g8 and the wR is self-protected, because if it is captured on h7 then it is reborn on h1 checking the bK.
 | Position 472_15 |
Now, another picture where the white Bishop is self-protected : Only the bK can capture on g2, but that means that it is exposed to check from the reborn on f1 bishop! Of course, if there was a piece on f1 (not a white pice that can control g2), then the bK is not mated but can capture the wB which would leave the chessboard.
 | Position 472_16 |
Let us put some more pieces on our chessboard. We suppose that black in a help-mate game chooses to castle. Then we have this interesting continuation :
 | Position 472_17 1.O-O Sxh6 [+bPh7]# |
In the next position White mates in two moves.
 | Position 472_18 1.Be2+! 1...Kg1 2.Bf2# 1...Kxe1[+wBc1] 2.Bd2# |
One of the variations has got a very peculiar picture.
 | Position 472_19 Mate it is! |
In the next bizzare position there exists a simple mate in one move. (Did you see it? We do not care if the wR and the wS seem to be captured with many ways...)
 | Position 472_20 |
Castling
Another significant difference of Circe from OTB chess is the possibility of the castling. If your King is still unmoved but your rooks are roaming around the chessboard, you definitely have abandoned the idea of castling...
But Circe allows castling with a reborn rook! It is a desirable effect. Can we form such a situation? Why not? We could maybe try to show both O-Ο and Ο-Ο-Ο in two variations. We choose again help-mate in two moves. The black King stands unmoved on e8. We leave empty the a8, h8 squares to be clear that the rooks have been moved, and that they might be reborn there. A white bishop can be useful in the diagonal a1-h8. (The h8 will be empty after Ο-Ο, and it is not easy to put a black piece there (but not impossible!). We could start like this :
 | Position 472_21 1.Rc3 Bxc3 [+bRh8] 2. O-O |
We can add white pieces and discover a mate somewhere, but what will be the function of the wB in the second variation, where we aim for Ο-Ο-Ο? We also think that the bR can be captured on f6, and that means we have more things to take care of ...
Well, we need additional material for White, and we have to aim at king's wing and queens's wing simultaneously. We will move wB some steps up the diagonal for sure. A white Rook is better idea than a white Queen. The rook will offer enough power to mate but not the excessive power of the queen, which in a helpmate has many chances to introduce many cooks (undesirable solutions) into our problem.
The wR will initially mate the bK on g8. But if wR is already on file g, castling is not allowed. Also, White must find a way to control f7, h7 squares. We could add pawns there, but we prefer to keep the position light. One idea is to put a white rook on f6, and capture a bR only on c3, but it does not allow castling, neither holds h7. If it is placed on the 7th row? It is supported by the wB, but h8 is not controlled. A black piece should go there after the castling.
But Black has finished its two moves! One by the rook to go where it must be captured, and another one the castling.
Ok, we shall send a black piece to h8! We will put a bR on g7, and then the wR can placed on file g. Let us try this :
 | Position 472_22 |
Two black rook will be captured on black squares and will be both rebornd on h8, the first to take part to the castling and the second to block the square h8.
i.e. 1.Rc3 Bxc3 [+bRh8] 2. O-O Rxg7 [+bRh8]#
But again, one rook can be captured on f6, and we still do not threaten anything thinking the variation Ο-Ο-Ο. Let us see it differently...
 | Position 472_23 |
The white pieces are threatening both file g and diagonal a1-h8. After the queen's-side castling, the bK will be on c8.
We examine the squares a8,b8, from which we can mate the bK. On a8, not easily, because it is white and we do not have white-squared bishop to control b7. If the white king takes control of b7, then the wB would sit unemployed, which is a great drawback for any problem.
But on b8? A wR there with the proper support will be what is needed. The b8 square is on file b2-b8 (which is cut by diagonal b2-h8) and on diagonal g3-b8 (which is cut by file g3-g8). We intentionally noted that the cuts are on the squares b2, g3.
We plan to put our pieces, wB and wR, there and they should move in each mentioned file and diagonal in two variations. Since the pieces are not queens, the solution would be the pieces to exchange places in the twin!
It is necessary for bRc6 also to change position. It must be captured on black square from a piece on b2, bishop or rook.
The b3 square is suitable. The bR on b3 is captured by wRb2, or it moves to c3 where it is captured by wBb2. It can not be placed further to the right to be captured there (on file-e it is captured with check, on g3 there is a wR blocking the way). We could place wRg1 and bRg3, but this breaks our twinning idea. But if the bR captures the wB on b2, Rxb2[+wBc1], and the be captured by the reborn bishop Bxb2[+bRh8], we would have an undesirable dual. So, we have discovered a nice square for the wK! Square c1. If the wB is captured on b2, it can not be reborn and gets out of the problem!
 | Position 472_24 |
Final Position.
 | Position 472_25 h#2, Circe, Twin with white pieces exchanging places. 1.Rc3+ Bxc3 [+bRh8] 2.O-O Rxg7 [+bRh8]# 1.Rd7 Rxb3 [+bRa8] 2.O-O-O Rb8# |
Question : Could we compose a similar problem without the twinning mechanism? With some rearrangement of white pieces, addition of a black pawn and with a little help from my good friends and able composers this can be done!
 | Position 472_26 h#2, Circe, 2111 |
We leave the 2 solutions to the reader. He/she is now familiar with the idea! (bRb3 is captured on b3 and c3).
A better position was published in 2002 by Zdenek Oliva, and we give him our compliments! (WinChloe 118771)
 | Position 472_27 Zdenek Oliva, Problemkiste 2002 h#2, Circe, 2 solutions 1.Rc6 Kxc6[+bRa8] 2.O-O-O Se7# 1.Rd4 Bxd4[+bRh8] 2.O-O Sh6# (But he could place bPh7 on h6 to have one more Circe-effect : 2.O-O Sxh6[+bPh7]#) |
The presentation stops here. We think that the message has been given.
Circe is simple, so try it!
(Editing / translation : Manolas Emmanuel)
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