+Can castle with Rook, moving 2 steps towards it
+
+Queen
+
+Q
+
+9.5
+
+RB or Q
+
+
+
+Rook
+
+R
+
+5
+
+R
+
+
+
+Bishop
+
+B
+
+3.25
+
+B
+
+Color-bound
+
+Knight
+
+N
+
+3.25
+
+N
+
+
+
+Pawn
+
+P
+
+1
+
+mfWcfF
+
+Promotes to Q, R, B, or N on reaching last rank
+
+
Pawn peculiarities
+
+
Pawns capture differently from how they move (straight move, diagonal capture).
+
Pawns can move two squares straight ahead from their initial position, provided they are not blocked.
+
On the move immediately after such a double push, they can be captured en passant by another Pawn,
+as if they had only moved 1 square ahead.
+
Pawns promote to another (non-royal) piece of choice when they reach last rank.
+
+
Castling
+
+A King that has not moved before can move two squares in the direction of a Rook that has not moved before,
+in which case that Rook is moved to the square the King skipped over.
+This is only allowed if all squares between King and Rook are empty,
+when the King is not in check on the square it came from,
+and would not be in check on any of the squares it skipped over.
+
+
General rules
+
+
It is not allowed to expose your King to capture.
+
The game is won by checkmating the opponent's King, or by checking it for the third time.
+
Stalemate (no legal moves, but not in check) is a draw.
+
+
Differences with FIDE
+
+You lose when being checked for the third time.
+
+
Strategy issues
+
+Bishops are confined to squares of a single color.
+Having Bishops on both colors compensates this weakness, and is worth an extra 0.5 on top of their added value.
+
+With Cambodian rules its first move can also be two steps forward
+
+Rook
+
+R
+
+5
+
+R
+
+
+
+Elephant
+
+B
+
+2.5
+
+FfW
+
+
+
+Knight
+
+N
+
+3.25
+
+N
+
+
+
+Pawn
+
+P
+
+1
+
+mfWcfF
+
+Promotes to Ferz on reaching last rank
+
+
Pawn peculiarities
+
+
Pawns capture differently from how they move (straight move, diagonal capture).
+
There is no initial double-push, and thus no en-passant capture.
+
Pawns promote to Ferz when they reach last rank; there is no choice.
+
+
General rules
+
+
It is not allowed to expose your King to check.
+
The game is won by checkmating the opponent's King.
+
Stalemate (no legal moves, but not in check) is a draw.
+
+
Differences with FIDE
+
+The Queen and Bishops are replaced by Ferz and Elephant.
+Pawns start on the third rank.
+Promotion always to Ferz.
+
+
Strategy issues
+
+It is not possible to force checkmate on a bare King with just a single Ferz, Elephant or Knight (in addition to your own King).
+Two Knights or two Ferzes cannot do it either.
+
+Can castle with Rook, moving 2 steps towards it
+
+Queen
+
+Q
+
+9.5
+
+RB or Q
+
+
+
+Rook
+
+R
+
+5
+
+R
+
+
+
+Bishop
+
+B
+
+3.25
+
+B
+
+Color-bound
+
+Knight
+
+N
+
+3.25
+
+N
+
+
+
+Pawn
+
+P
+
+1
+
+mfWcfF
+
+Promotes to Q, R, B, or N on reaching last rank
+
+
Pawn peculiarities
+
+
Pawns capture differently from how they move (straight move, diagonal capture).
+
Pawns can move two squares straight ahead from their initial position, provided they are not blocked.
+
On the move immediately after such a double push, they can be captured en passant by another Pawn,
+as if they had only moved 1 square ahead.
+
Pawns promote to another (non-royal) piece of choice when they reach last rank.
+
+
Castling
+
+A King that has not moved before can move two squares in the direction of a Rook that has not moved before,
+in which case that Rook is moved to the square the King skipped over.
+This is only allowed if all squares between King and Rook are empty,
+when the King is not in check on the square it came from,
+and would not be in check on any of the squares it skipped over.
+
+
General rules
+
+
Captures destroy ('explode') both capturer and victim, and also destroy all non-Pawns adjacent to the capture square.
+
The game is won by destroying the opponent's King.
+
Destroying your own King is not allowed.
+
Stalemate (no legal moves, but not in check) is a draw.
+
+
Differences with FIDE
+
+Pieces explode on capture, destroying everything in the area including themselves.
+You win by destroyig the King rather than checkmating it;
+exposing your King to destruction is not forbidden (just stupid).
+
+
Strategy issues
+
+Since any capturing piece destroys itself in the explosion, Kings can never capture.
+
+
+A King taking shelter next to the opponent's King (which, after all, cannot capture)
+is immune to capture, as such a capture would destroy your opponent's King in the explosion.
+So many end-games (even KQK) can be drawn by tailing the opponnet's King!
+
+Can castle with Rook, moving 2 steps towards it
+
+Queen
+
+Q
+
+9.5
+
+RB or Q
+
+
+
+Rook
+
+R
+
+5
+
+R
+
+
+
+Bishop
+
+B
+
+3.25
+
+B
+
+Color-bound
+
+Knight
+
+N
+
+3.25
+
+
+
+N
+
+Berolina Pawn
+
+P
+
+1
+
+mfFcfW
+
+Promotes to Q, R, B, or N on reaching last rank
+
+
Pawn peculiarities
+
+
Pawns capture differently from how they move (diagonal move, straight capture).
+
Pawns can move two squares diagonally ahead from their initial position, provided they are not blocked.
+
On the move immediately after such a double push, they can be captured en passant by another Pawn,
+as if they had only moved 1 square ahead.
+
A diagonal move to the square skipped by the previous Pawn move is thus not an e.p. capture.
+
Pawns promote to another (non-royal) piece of choice when they reach last rank.
+
+
Castling
+
+A King that has not moved before can move two squares in the direction of a Rook that has not moved before,
+in which case that Rook is moved to the square the King skipped over.
+This is only allowed if all squares between King and Rook are empty,
+when the King is not in check on the square it came from,
+and would not be in check on any of the squares it skipped over.
+
+
General rules
+
+
It is not allowed to expose your King to check.
+
The game is won by checkmating the opponent's King.
+
Stalemate (no legal moves, but not in check) is a draw.
+
+
Differences with FIDE
+
+The capture and non-capture move of the Pawns have been swapped. As a result the initial double-push is also diagonal.
+
+
Strategy issues
+
+It is not possible to force checkmate on a bare King with just a single Bishop or Knight (in addition to your own King).
+Two Knights cannot do that either.
+
+
+Bishops are confined to squares of a single color.
+Having Bishops on both colors compensates this weakness, and is worth an extra 0.5 on top of their added value.
+
+Ralph Betza invented a compact notation to encode moves of a piece,
+which is now in wide-spread use for description of Chess variants.
+This page describes a version of it that has been extended in several ways.
+Some of these extensions were embraced from another proposed extension scheme,
+'Bex notation' by David Howe, others are entirely new.
+These new extensions from the original Betza notation are marked in yellow.
+
+Betza notation decomposes the piece into 'atoms',
+which represent the set of all (8-fold-)symmetry-equivalent moves of a certain distance.
+For example all eight Knight moves, or all diagonal moves of the King.
+Each 'atom' is written as a single capital (e.g. N for the Knight moves),
+which is very efficient when you are dealing with pieces that are maximally symmetric
+(which most pieces indeed are).
+Atoms refer to single unblockable leaps of a certain distance.
+Pieces that can repeat the same leap again and again until they encounter an obstacle
+(sliders or riders, such as Rook)
+are very common.
+Those moves are indicated by writing the number of steps the piece can maximally make behind the atom,
+where '0' can be used to indicate 'any number of steps'.
+
+
+The choice to treat moves as sets that go in all directions goes at the expense of the compactness when dealing with asymmetric pieces.
+(This is a cheap price to pay, as asymmetric pieces are much less common than fully symmetric ones.)
+To describe moves of asymmetric pieces Betza notation uses lower-case prefixes to identify which sub-set of the atom we mean.
+Such as f (forward) or r (right), or combinarions of those like fr.
+E.g. fR decribes a 'Rook' that only moves in the forward direction (i.e., the Shogi Lance).
+Lower-case prefixes are also used to specify the move is not a general one
+(i.e. valid as capture and non-capture, the normal situation in Chess-like games),
+but can only be used in limited ways (e.g. capture only, non-jumping, capture after jumping).
+
+
The basic atoms
+
+
+The following table describes the most important atoms
+
+
+Atom
+
+Vector
+
+Piece
+
+O
+
+(0,0)
+
+Null move (Taikyoku-Shogi Lion can do this)
+
+W
+
+(1,0)
+
+Wazir (Courier Chess)
+
+F
+
+(1,1)
+
+Ferz (Shatranj)
+
+D
+
+(2,0)
+
+Dababba
+
+A
+
+(2,2)
+
+Alfil (Shatranj)
+
+I
+
+(3,0)
+
+Tripper
+
+L
+
+(3,1)
+
+Long Knight (aka Camel)
+
+J
+
+(3,2)
+
+Zebra
+
+G
+
+(3,3)
+
+
+
+
+
+Laid out on the board, (standing at O), the move encoding is as follows:
+
+.
.
.
.
.
.
.
.
.
+
+.
G
J
L
H
L
J
G
.
+
+.
J
A
N
D
N
A
J
.
+
+.
L
N
F
W
F
N
L
.
+
+.
H
D
W
O
W
D
H
.
+
+.
L
N
F
W
F
N
L
.
+
+.
J
A
N
D
N
A
J
.
+
+.
G
J
L
H
L
J
G
.
+
+.
.
.
.
.
.
.
.
.
+
+
+
+
+For longer-range atoms no letters are defined.
+In the rare cases they occur, these can be written using the numeric coordinates of their leap vector,
+e.g. (4,1) for the Giraffe leap.
+Note this still implies the move goes in all directions (i.e. (4,1) also means (4,-1), (-4,1), (1,4), ...),
+and thus still does a lot for compactness.
+A piece that only leaps 4 forward and 1 left or right would be an f(4,1).
+
+
+
Modifier prefixes
+
+The following table lists possible prefixes to the atoms.
+Prefixes can be combined, in which case the sub-sets of move types they correspond to are joined.
+E.g. fb means forward and backward moves (but not sideways).
+So even prefixes with opposite meaning are not really conflicting;
+they could be superfluous, however.
+(E.g. mc would mean both non-capture and capture, which is the default in absence of prefixes anyway.)
+
+
+prefix
+
+short for
+
+meaning
+
+Move modality
+
+c
+
+capture
+
+Captures only
+
+m
+
+move
+
+Move but not capture
+
+Move blocking
+
+n
+
+non-jumping
+
+Cannot jump over occupied square
+
+j
+
+jump one
+
+Must jump exactly one
+
+jj
+
+jump many
+
+Can jump over any number of pieces
+
+Hopping
+
+p
+
+Pao (=Canon)
+
+(Obsolete?) Capture if move jumps over one obstacle, non-capture if it does not jump
+
+g
+
+Grasshopper
+
+(Obsolete?) Must land directly behind first obstacle
+
+q
+
+Circular
+
+(Obsolete?) Basic step repeated at an angle, until it closes on itself
+
+z
+
+Zig-zag
+
+(Obsolete?) Repeat step alternates angle between two values.
+
+o
+
+
+
+wraps around on cylinder board
+
+directional-subset and other geometry indicators
+
+f
+
+forward
+
+most-forward single or pair of moves of symmetry-equivalent moves
+
+b
+
+backward
+
+most-backward single or pair of moves of symmetry-equivalent moves
+
+l
+
+left
+
+left-most single or pair of moves of symmetry-equivalent moves
+
+r
+
+right
+
+right-most single or pair of moves of symmetry-equivalent moves
+
+s
+
+sideways
+
+short for lr
+
+v
+
+vertical
+
+short for fb
+
+a
+
+all
+
+short for vs (default on atoms specifying complete move, but can be needed in chaining)
+
+ff
+
+forward
+
+obsolete notation for forward-most two of 8 symmetry-equivalent moves
+
+fh
+
+forward half
+
+forward-most four of 8 symmetry-equivalent moves
+
+fs
+
+sideway-forward
+
+fh but not f
+
+etc.
+
+
+
+Similar for b (bb, bh, bs), l and r
+
+i
+
+initial
+
+Initial move only (for pieces that have not moved yet)
+
+e
+
+equal
+
+equal in length to previous step, measured in board steps (see section on chaining)
+
+
+For example, fmWfcF is a Pawn: non-captures forward to a W square, captures to the two forward F squares.
+Pretty complicated, but the Pawn is a very complex piece (asymmetric, and divergent capture/non-capture).
+Note that fr and rf are not the same on 'oblique' (= not orthogonal or diagonal) atoms, which have 8 moves,
+and that they might not be what you intuitively think, as fs = fl + fr.
+
Grouping
+
+Grouping of atoms, modifiers and exponents is possible with parentheses.
+This can be done for readability,
+or for overruling operator priorities.
+(fmW)(fcF) might read more easily than fmWfcF.
+The parentheses do not have any meaning in themselves.
+'Distributivity' also works for modifier prefixes:
+m(AB) where m is a string of modifiers and A and B are atoms, (or expressions grouped in parentheses),
+is defined to mean mAmB.
+Some shortcuts for commonly used combinations of atoms exist;
+these can be seen as implicit grouping of the involved atoms.
+
+
+shortcut
+
+stands for
+
+orthodox piece
+
+K
+
+WF
+
+King
+
+B
+
+F0 (FF)
+
+Bishop
+
+R
+
+W0 (WW)
+
+Rook
+
+Q
+
+RB
+
+Queen
+
+C
+
+L
+
+Camel
+
+Z
+
+J
+
+Zebra
+
+
+
Chaining moves
+
+When a number of atoms is concatenated, like WF, it joins their move sets.
+So the piece described by WF moves either as W or as F, i.e. one step diagonal, or one step orthogonal.
+That means it is the King of orthodox Chess!
+(From the notation you cannot see whether it is royal yet;
+the main purpose of the notation is to convey how it moves.
+But a 'k' prefix could be used to indicate royalty, when this is of relevance.)
+
+
+It is also possible to specify that certain moves have to be performed sequentially, one after the other.
+For instance because something of importance happens or should be noted on an intermediate square.
+Such as for pieces that can be blocked on squares they cannot visit ('lame leapers'),
+or that have to hop over other pieces in a specific pattern.
+The simplest example of this, however, is repetition of the same step in the same direction,
+as in sliding or riding pieces, such as a Rook.
+The far moves of such a piece can indeed be blocked by an obstacle closer by on their path,
+although it can then always reach that square itself as well.
+Such moves are indicated by 'exponentiation': a number after the atom indicates how often the step may be repeated.
+E.g. F3 would be a piece that slides diagonally (i.e. like a Bishop), upto a maximum of 3 steps.
+To indicate an arbitrary number of steps can be taken, we use 0 (zero) for the exponent.
+(This because infinity is not in the ASCII character set, and 0 would be pointless when taken at face value.)
+So W0 would be the Rook, sliding arbitrarily far orthogonally, and F0 the Bishop.
+(Old notation for this would be WW and FF, but in the extended context these would be troublesome.)
+
+Not all multi-step moves are as regular as simple sliders, however.
+Some 'bent' sliders can turn corners, for instance.
+The 'Griffon' is an example that first moves one step diagonally, and then continues outward as a Rook.
+It does not have to go beyond the corner, though; just like a normal Rook it can make the first step of its move only.
+And if it encounters something on that first step, it is blocked, and never gets to the rooky part of its move.
+To describe this trajectory we cannot use exponentiation, but have to explicitly write the chain: FtR.
+Here the 't' is the chaining operator, that distinguishes this from FR,
+which would mean a piece that steps one diagonally or moves like Rook (a Shogi Dragon Horse).
+The 't' is because of 'and then', but also because the move could be terminated at that point,
+and there is no requirement to visit the later parts of the specified trajectory.
+
+
+There are other forms of chaining, where the 'connecting square' can not be visited.
+(I.e. no termination there.)
+The Xiangqi Horse moves one orthogonal step, and then (without stopping) one step diagonally outward,
+mimicking the move of a Knight, but blockable on the intermediate square.
+This is written as the chain W-F.
+The chaining operator '-' indicates the move cannot be terminated at that point (ending on the connection square),
+but must continue.
+If it cannot, because the square was occupied, the move described by the chain is considered blocked, and cannot be made.
+
+
+Overview of chaining operators
+
+
t
then
terminate on connection square (if empty or enemy) or continue (if empty).
+
-
block
must continue if connection square empty; otherwise entire path is considered blocked
+
+
hop
connection square must be occupied and remains untouched; move must go on from there
+
?
own
connection square must contain own piece and remains untouched; move must go on from there
+
!
foe
connection square must contain enemy and remains untouched; move must go on from there
+
x
capture
connection square must contain enemy, which is captured; move must go on from there
+
d
destroy
connection square must be occupied, friend or foe there is destroyed; must go on
+
y
split
connection square is one step before first obstacle; must continue from there
+
+
+Chaining implies continuation in the most similar direction.
+Should you need to deviate from that, e.g. because the trajectory doubles back on itself,
+directional modifiers must be used.
+The continuation steps are to be described in a coordinate system relative to the previous step, however.
+So W-rW-lW makes one step, (say moving North), then turns right for another step (moving East), and then turns left compared to that second step,
+meaning it is moving North again!
+So in the end you arrive at (1,2), over (0,1) and (1,1).
+This is a Knight move that can only be made if both the intermediate squares are empty,
+even worse than the Xiangqi Horse (which at least did not care about (1,1))!
+The latter would be described by W-F.
+The F after '-' would by default mean fF, and in the orientation of the preceding orthogonal step
+this would imply a pair of outward moves, fl + fr.
+
+
+Some examples that use the other operators:
+Q+K is the Grasshopper: it must move as Queen to an occupied square (the 'support'),
+(the first one it encounters, as Queens do not jump!),
+and then continue with a single K step in the same direction (leaving the occupant of the square alone),
+to land on the square directly behind the support.
+where it can capture or just move.
+mRcR+R is the Xiangqi Cannon: the first mR specifies its non-capture move, which is that of a normal Rook.
+The concatenated cR+R is the capturing alternative;
+it moves as R to an occupied square, and then continues as R in the same direction for a capture.
+Note that the 'c' prefix applies to the complete R+R path (a once jumping Rook);
+the operator priorities are such that the binary operators t-+xdy couple more tightly than the prefix modifiers mc.
+The latter are only allowed in front of a complete path, to specify what you can do at the end of it,
+and not on individual steps of the path, where the chaining operators already specify this.
+
+
Weird captures
+
+The x operator allows description of pieces with unconventional capture,
+as it specifies moving away from the capture square.
+Normal in Chess is of course that you only captured what was on the square you end on.
+But even in orthodox Chess e.p. capture exists as an exception to that.
+It could be written as frmWxlW, which, as we have seen, means frm(WxlW)
+This expreses capture through a W step, and then turning left for a second W step,
+so that overall you make an F step in an L form.
+The frm prefix to this F step means that it can not capture on the final square
+(the Pawn in e.p. capture always goes to an empty square),
+to your forward right.
+I.e. you started moving right, then turned left to move forward.
+So the continuation square you pass over to remove the Pawn is to your right.
+(There is no way to express that you can only do this to Pawns, however, let alone to Pawns that just made a double push.)
+
+
+This shows the general encoding strategy: if you capture pieces not on your destination square, as 'side effect' to the move,
+you lay out a path that tramples all the pieces that are captured, so that the sub-steps are all normal replacement captures.
+E.g. a Checker would be fmFfmFxF. There the fmF part is the non-capture move,
+but the interesting part is the capture:
+one step diagonal (which must be to an occupied square, which we capture),
+and then straight on (which is now 'forward' in the local frame of reference set up by the first step)
+to the next square, for an overall A step.
+This step must be fmA, i.e. in one of the forward diagonal directions, not capturing anything on the square where it lands.
+'Rifle capture' by a Rook would be RxebR, i.e. first capture something in the normal way,
+and then manditorily withdraw in the direction from which you came (b) by an R move of the same length.
+No overall move, but the victim is gone!
+A Ultima Withdrawer, which destroys the adjacent piece from which it moves away, would be written as
+mQmKxbK-Q. The capture part, m(KxbK-Q) specifies capture to the adjacent piece, reversing that step (b) to your square of origin,
+and then mandatorily continuing in that direction with a Queen non-capture move (the victim already in your pocket).
+The hit-and-run or double capture of a Lion would be KxaK: capture the adjacent piece,
+after which you must continue by another King step in any direction relative to the first, capturing a second victim or just moving.
+ven the rifle capture (igui) is included in this.
+Its turn-passing move would be K-bK.
+Which is different from O, because it can only be done if the Lion is adacent to an empty square,
+while a piece that has an O atom can pass uncondiionally.
+For definiteness, when directional modifiers apply to a path that results in a return to the starting square,
+they will be referenced to the direction of the first step of the path.
+
+
More about exponentiation
+
+Exponentiation by default implies repeated application of the 't' operator.
+But it can be used to indicate repeate application of other operators too.
+We define AmN, with A an atom or a group within parentheses, m a string of modifiers, and N a number,
+to mean AmAmAm...mA with N factors A and N-1 operators between them.
+If the modifier string m does not contain one of the chaining operators, it is prefixed with the default 't'.
+If it does not include any directional modifiers, it is suffixed with 'f'.
+So W3 means WtfWtfW, 1 to 3 orthogonal steps in the same direction (which is what the 'f' specifies).
+But W-3 would mean W-fW-fW, which is exactly 3 such steps.
+And Wx3 would be exactly 3 steps where the first 2 mandatorily capture.
+
+
+By including directonal indicators, you can describe curved trajectories.
+Nrf8 would mean NtrfNtrfN..., upto 8 Knight moves, each consecutive move bending ~45 degrees right from the previous one
+(because that is what rf means; the first opportnity to the right that is not straight ahead).
+This describes the Rose!
+Circular riders fit into the system, and there is no need for a separate prefix to describe them.
+With grouping you can do more: (FtlF)r0 expands to FtlFtrFtlFtrFtl..., an arbitrary number of diagonal steps,
+that alternately turn 90 degrees left or right.
+In other words, the Crooked Bishop.
+There is also no real need for the z prefix in this extended Betza notation.
+The exponentiation can describe it much more precisely,
+specifying exactly how Crooked it is.
+
+There is no fixed setup;
+the back-rank pieces are randomly shuffled with certain restrictions.
+Black's setup is the mirror image of white's, though.
+Both sides have:
+
+The Bishops must start on different colors.
+The King must start between the Rooks.
+It has been suggested the Bishops should also not start next to each other.
+
+
+
+
Moves at a Glance
+
+
Click on a piece below to see its moves
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Sliding capture or non-capture, can be blocked on any square along the ray
+Can castle with Rook, moving 3 steps towards it
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+Queen
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+Q
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+9.5
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+RB or Q
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+Chancellor
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+C
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+9
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+RN
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+ArchBishop
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+A
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+8.75
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+BN
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+Rook
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+R
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+5
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+R
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+Bishop
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+B
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+3.5
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+B
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+Color-bound
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+Knight
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+N
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+3
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+N
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+Pawn
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+P
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+1
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+mfWcfF
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+Promotes to Q, R, B, or N on reaching last rank
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Pawn peculiarities
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Pawns capture differently from how they move (straight move, diagonal capture).
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Pawns can move two squares ahead from their initial position, provided they are not blocked.
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On the move immediately after such a double push, they can be captured en passant by another Pawn,
+as if they had only moved 1 square ahead.
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Pawns promote to another (non-royal) piece of choice when they reach last rank.
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Castling
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+A King that has not moved before can move to the c1/c8 or i1/i8 in the direction of a Rook that has not moved before,
+in which case that Rook is moved to the square on the other side next to the King.
+This is only allowed if all squares traveled through by King and Rook are empty (after their removal),
+when the King is not in check on the square it came from,
+and would not be in check on any of the squares it skipped over.
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General rules
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It is not allowed to expose your King to check.
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The game is won by checkmating the opponent's King.
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Stalemate (no legal moves, but not in check) is a draw.
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+You can use the New Shuffle dialog to control the randomization of the initial position.
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Differences with FIDE
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+The Chancellor and Archbishop pieces are extra, and the board is expanded to accomodate them.
+Castling is generalized to allow it with non-standard placement of King and Rooks.
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Strategy issues
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+It is not possible to force checkmate on a bare King with just a single Bishop or Knight (in addition to your own King).
+Two Knights cannot do that either.
+The Archbishop can force checkmate against a bare King.
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+Bishops are confined to squares of a single color.
+Having Bishops on both colors compensates this weakness, and is worth an extra 0.5 on top of their added value.
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+As Chancellor and Queen are nearly equal in value to Queen, under-promotion is very common,
+and there is virtually never any need to promote to R, B or N.
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+The super-pieces (Q, C, A) devaluate by the presence of lower-valued opponent pieces.
+As a result trading Q for R + B is in general a good trade when you still have both J,
+as the latter gain in value by eliminating the opponent's R and B,
+which is more compensation than the intrinsic value differene between Q and R + B.
+