--- /dev/null
+p.boxed
+ | Most pieces look the same but behave very differently.
+ | They generally move like an orthodox queen,
+ | but capturing rules are complex.
+
+p
+ | Note: 'Baroque' is the initial name thought by the author,
+ | but 'Ultima' is also largely adopted.
+ a(href="https://www.chessvariants.com/people.dir/abbott.html")
+ | He prefers 'Baroque'
+ | , and I think me too.
+
+h3 Specifications
+
+ul
+ li Chessboard: standard.
+ li Material: "standard".
+ li Non-capturing moves: often like queen.
+ li Special moves: none.
+ li Captures: very special.
+ li End of game: standard; see below.
+
+h4 Pieces names
+
+p Pieces names refer to the way they capture, which is described later.
+ul
+ li Pawn : pawn or pincer
+ li Rook : coordinator
+ li Knight : long leaper
+ li Bishop : chameleon
+ li Queen : withdrawer
+ li King : king (same behavior as in standard chess)
+p.
+ Besides, a new piece is introduced: the immobilizer, written by the letter 'm'
+ in FEN diagrams and PGN games. It is represented by an upside-down rook:
+
+figure.diagram-container
+ .diagram
+ | fen:8/8/4m3/8/8/8/3M4/8:
+ figcaption Immobilizers on d2 and e6.
+
+h3 Non-capturing moves
+
+p.
+ Pawns move as orthodox rooks, and the king moves as usual,
+ one square in any direction.
+ All other pieces move like an orthodox queen.
+
+p.
+ When a piece is adjacent to an enemy immobilizer, it cannot move unless
+ the enemy immobilizer is adjacent to a friendly immobilizer or chameleon
+ (cancelling the powers of the opponent's immobilizer).
+p
+ | Note : this corresponds to the "pure rules" described on
+ a(href="http://www.inference.org.uk/mackay/ultima/ultima.html") this page
+ | , which slightly differ from the initial rules.
+ | The aim is to get rid of the weird suicide rule by weakening the immobilizers lock.
+ | In particular, in the original rules two adjacent immobilizer are stuck forever
+ | until one is captured. Note that it's still the case if all chameleons disappeared.
+
+h3 Capturing moves
+
+p.
+ Easy case first: the king captures as usual, by moving onto an adjacent square
+ occupied by an enemy piece. But this is the only piece following orthodox rules,
+ and also the only one which captures by moving onto an occupied square.
+ All other pieces capture passively: they land on a free square and captured
+ units are determined by some characteristics of the movement.
+
+p Note 1: the immobilizer does not capture.
+
+p.
+ Note 2: for passive captures, a 'X' is added at the end of the move notation,
+ to indicate that something was taken (replaying the game is necessary to know where).
+
+h4 Pawns/Pincers
+
+p.
+ If at the end of its movement a pawn is horizontally or vertically adjacent to an
+ enemy piece, which itself is next to a friendly piece (in the same direction),
+ the "pinced" unit is removed from the board.
+
+figure.diagram-container
+ .diagram
+ | fen:7k/5ppp/2N5/2n5/3rB3/8/PPP5/K7:
+ figcaption 1.Pc2c4 captures both coordinator and long leaper.
+
+h4 Coordinators (rooks)
+
+p.
+ Imagine that rook and king of the same color are two corners of a rectangle
+ (this works if these two pieces are unaligned).
+ If at the end of a rook move an enemy piece stands in any of the two remaining
+ corners, it is captured.
+
+figure.diagram-container
+ .diagram
+ | fen:8/2b4K/2q5/3p1N1p/8/8/2R5/k7:
+ figcaption 1.Rc5 captures on c7 and h5.
+
+h4 Long leapers (knights)
+
+p.
+ A knight captures exactly as a queen in international draughts game: by jumping
+ over its enemies, as many times as it can/want but always in the same direction.
+ In this respect it is less powerful than a draughts' queen:
+ on the following diagram c8 or f6 cannot be captured.
+ However, the knight does not have to maximize the number of captured units
+ (as is the case in draughts).
+
+figure.diagram-container
+ .diagram
+ | fen:2n4k/3r4/5b2/3p4/1m6/3b4/3N4/K7 d4,d6,d8,a5:
+ figcaption All marked squares captures are playable from d2.
+
+h4 Withdrawer (queen)
+
+p.
+ The queen captures by moving away from an adjacent enemy piece, in the opposite
+ direction (without jumping, the path must be free).
+
+figure.diagram-container
+ .diagram
+ | fen:7k/8/8/3Qr3/8/8/8/K7 a5,b5,c5:
+ figcaption 1.Qa5, 1.Qb5 or 1.Qc5 captures the black rook.
+
+h4 Chameleon (bishop)
+
+p The chameleon captures pieces in the way they would capture. So, it
+ul
+ li pinces pawns (if moving like a pawn),
+ li withdraws from withdrawers,
+ li leaps over long leapers,
+ li coordinates coordinators.
+p ...and these captures can be combined.
+
+p.
+ Remark: the move indicated on the diagram doesn't capture the black pincer
+ on e5, since it is a diagonal move (not like a pawn).
+
+figure.diagram-container
+ .diagram
+ | fen:7k/8/8/r3pP2/2n5/8/B7/K7 a5,c4:
+ figcaption 1.Bd5 captures the two marked pieces.
+
+p.
+ Besides, chameleon immobilizes immobilizers (but cannot capture them since they
+ do not capture).
+
+p.
+ A chameleon captures the king in the same way the king captures, which means that
+ a chameleon adjacent to a king gives check.
+
+h3 End of the game
+
+p.
+ Checkmate or stalemate as in standard chess. Note however that checks are more
+ difficult to see, because of the exotic capturing rules. For example, on the
+ following diagram the white king cannot move to e5 because then
+ the black pawn could capture by moving next to it.
+
+figure.diagram-container
+ .diagram
+ | fen:7k/8/8/p4r/4K3/8/8/8 e5:
+ figcaption 1.Ke5 is impossible
+
+h3 More information
+
+p.
+ | A good starting point is the
+ a(href="https://en.wikipedia.org/wiki/Baroque_chess") Wikipedia page
+ | , which also gives pointers to other interesting pages (including
+ | chessvariants.com, as usual).
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