Click here to open/close a piece overview. Play it!
The AI will now respond to your moves! ( + 2.5 ply - )
Info for selected board piece
mc
Move or capture
mc
Move or capture (unblockable jump)
m
Move only
im
Move only (unmoved piece only)
c
Capture only
O
Castling destination of King
m,c
Forbidden move, but delivers check
?
p,g
Hop target (hover/touch for actual move)
Click on piece to toggle its moved status
Click on piece name to see its move diagram. (print version)
ID
white
nr
black
nr
name
move
P
-
-
pawn
fceFifmnDifmnHfmW
V
-
-
vao
mBcpB
N
4
4
knight
N
W
-
-
wizard
FC
B
4
4
bishop
B
C
-
-
cannon
mRcpR
S
-
-
champion
WAD
R
4
4
rook
R
A
-
-
archbishop
BN
M
-
-
marshall
RN
Q
2
2
queen
Q
K
-
-
king
KisO4isO3isO2
Gross Chess
The 'diagram of the week' is for Gross Chess, a large-board variant that complements the FIDE army with some fairy pieces known from several other popular variants: the Archbishop and Chancellor from Capablanca Chess, the Champion and Wizard from Omega Chess, and the Cannon from Xiangqi plus its diagonal cousin, the Vao.
Click below to display piece moves:
Pawn (a3-l3; a10-l10)
Vao (c1,j1; c12,j12)
Knight (d2,i2; d11,i11)
Wizard (d1,i1; d12,i12)
Bishop (e2,h2; e11,h11)
Cannon (e1,h1; e12,h12)
Champion (c2,j2; c11,j11)
Rook (b2,k2; b11,k11)
Archbishop (b1,k1; b12,k12)
Marshall (a1,l1; a12,l12)
Queen (f2; f11)
King (g2; g11)
The moves of most pieces are not very special,
and have very basic descriptions in Betza notation,
all supported by the Interactive Diagram script.
The main challenge was in the promotion rules.
The diagram allows you to specify a list of legal promotion choices,
and even allow you to specify that these pieces come from holdings
that accumulate captured pieces,
as well as some pieces that start there.
But has no standard mechanism for making this choice rank-dependent.
For this a small extra script routine had to be added,
which corrects any invalid choice to a non-promotion.
The flexible castling is achieved in the diagram by specifying all possible different castlings as separate moves on the King: isO2, isO3 and isO4. This is needed because unlike with other Betza atoms, a range specifier on the O atom in the XBetza extension used in the diagram indicates an exact range, rather than a maximum. That the castling partner is not at the board edge poses no special problem, because the diagram always allows castling with a virgin piece that moves as a Rook. (Which actually is in violation of the XBetza specs, which would need an extra j modifier to specify the castling partner is one square away from the board edge. But which is almost always what you want.)
Interactive diagram: pieces movable, right-click resets!
Click here to open/close a piece overview. Play it!
Gross Chess
The 'diagram of the week' is for Gross Chess, a large-board variant that complements the FIDE army with some fairy pieces known from several other popular variants: the Archbishop and Chancellor from Capablanca Chess, the Champion and Wizard from Omega Chess, and the Cannon from Xiangqi plus its diagonal cousin, the Vao.
The moves of most pieces are not very special, and have very basic descriptions in Betza notation, all supported by the Interactive Diagram script. The main challenge was in the promotion rules. The diagram allows you to specify a list of legal promotion choices, and even allow you to specify that these pieces come from holdings that accumulate captured pieces, as well as some pieces that start there. But has no standard mechanism for making this choice rank-dependent. For this a small extra script routine had to be added, which corrects any invalid choice to a non-promotion.
The flexible castling is achieved in the diagram by specifying all possible different castlings as separate moves on the King: isO2, isO3 and isO4. This is needed because unlike with other Betza atoms, a range specifier on the O atom in the XBetza extension used in the diagram indicates an exact range, rather than a maximum. That the castling partner is not at the board edge poses no special problem, because the diagram always allows castling with a virgin piece that moves as a Rook. (Which actually is in violation of the XBetza specs, which would need an extra j modifier to specify the castling partner is one square away from the board edge. But which is almost always what you want.)