2 | Most pieces look the same but behave very differently.
3 | They generally move like an orthodox queen,
4 | but capturing rules are complex.
7 | Note: 'Baroque' is the initial name thought by the author,
8 | but 'Ultima' is also largely adopted.
9 a(href="https://www.chessvariants.com/people.dir/abbott.html")
10 | He prefers 'Baroque'
11 | , and I think me too.
16 li Chessboard: standard.
17 li Material: "standard".
18 li Non-capturing moves: often like queen.
19 li Special moves: none.
20 li Captures: very special.
21 li End of game: standard; see below.
25 p Pieces names refer to the way they capture, which is described later.
27 li Pawn : pawn or pincer
29 li Knight : long leaper
32 li King : king (same behavior as in standard chess)
34 Besides, a new piece is introduced: the immobilizer, written by the letter 'm'
35 in FEN diagrams and PGN games. It is represented by an upside-down rook:
37 figure.diagram-container
39 | fen:8/8/4m3/8/8/8/3M4/8:
40 figcaption Immobilizers on d2 and e6.
42 h3 Non-capturing moves
45 Pawns move as orthodox rooks, and the king moves as usual,
46 one square in any direction.
47 All other pieces move like an orthodox queen.
50 When a piece is adjacent to an enemy immobilizer, it cannot move unless
51 the enemy immobilizer is adjacent to a friendly immobilizer or chameleon
52 (cancelling the powers of the opponent's immobilizer).
54 | Note : this corresponds to the "pure rules" described on
55 a(href="http://www.inference.org.uk/mackay/ultima/ultima.html") this page
56 | , which slightly differ from the initial rules.
57 | The aim is to get rid of the weird suicide rule by weakening the immobilizers lock.
58 | In particular, in the original rules two adjacent immobilizer are stuck forever
59 | until one is captured. Note that it's still the case if all chameleons disappeared.
64 Easy case first: the king captures as usual, by moving onto an adjacent square
65 occupied by an enemy piece. But this is the only piece following orthodox rules,
66 and also the only one which captures by moving onto an occupied square.
67 All other pieces capture passively: they land on a free square and captured
68 units are determined by some characteristics of the movement.
70 p Note 1: the immobilizer does not capture.
73 Note 2: for passive captures, a 'X' is added at the end of the move notation,
74 to indicate that something was taken (replaying the game is necessary to know where).
79 If at the end of its movement a pawn is horizontally or vertically adjacent to an
80 enemy piece, which itself is next to a friendly piece (in the same direction),
81 the "pinced" unit is removed from the board.
83 figure.diagram-container
85 | fen:7k/5ppp/2N5/2n5/3rB3/8/PPP5/K7:
86 figcaption 1.Pc2c4 captures both coordinator and long leaper.
88 h4 Coordinators (rooks)
91 Imagine that rook and king of the same color are two corners of a rectangle
92 (this works if these two pieces are unaligned).
93 If at the end of a rook move an enemy piece stands in any of the two remaining
94 corners, it is captured.
96 figure.diagram-container
98 | fen:8/2b4K/2q5/3p1N1p/8/8/2R5/k7:
99 figcaption 1.Rc5 captures on c7 and h5.
101 h4 Long leapers (knights)
104 A knight captures exactly as a queen in international draughts game: by jumping
105 over its enemies, as many times as it can/want but always in the same direction.
106 In this respect it is less powerful than a draughts' queen:
107 on the following diagram c8 or f6 cannot be captured.
108 However, the knight does not have to maximize the number of captured units
109 (as is the case in draughts).
111 figure.diagram-container
113 | fen:2n4k/3r4/5b2/3p4/1m6/3b4/3N4/K7 d4,d6,d8,a5:
114 figcaption All marked squares captures are playable from d2.
116 h4 Withdrawer (queen)
119 The queen captures by moving away from an adjacent enemy piece, in the opposite
120 direction (without jumping, the path must be free).
122 figure.diagram-container
124 | fen:7k/8/8/3Qr3/8/8/8/K7 a5,b5,c5:
125 figcaption 1.Qa5, 1.Qb5 or 1.Qc5 captures the black rook.
127 h4 Chameleon (bishop)
129 p The chameleon captures pieces in the way they would capture. So, it
131 li pinces pawns (if moving like a pawn),
132 li withdraws from withdrawers,
133 li leaps over long leapers,
134 li coordinates coordinators.
135 p ...and these captures can be combined.
138 Remark: the move indicated on the diagram doesn't capture the black pincer
139 on e5, since it is a diagonal move (not like a pawn).
141 figure.diagram-container
143 | fen:7k/8/8/r3pP2/2n5/8/B7/K7 a5,c4:
144 figcaption 1.Bd5 captures the two marked pieces.
147 Besides, chameleon immobilizes immobilizers (but cannot capture them since they
151 A chameleon captures the king in the same way the king captures, which means that
152 a chameleon adjacent to a king gives check.
157 Checkmate or stalemate as in standard chess. Note however that checks are more
158 difficult to see, because of the exotic capturing rules. For example, on the
159 following diagram the white king cannot move to e5 because then
160 the black pawn could capture by moving next to it.
162 figure.diagram-container
164 | fen:7k/8/8/p4r/4K3/8/8/8 e5:
165 figcaption 1.Ke5 is impossible
170 | A good starting point is the
171 a(href="https://en.wikipedia.org/wiki/Baroque_chess") Wikipedia page
172 | , which also gives pointers to other interesting pages (including
173 | chessvariants.com, as usual).