Commit | Line | Data |
---|---|---|
32cfcea4 | 1 | p.boxed |
2f3c8451 | 2 | | Most pieces look the same but behave very differently. |
32cfcea4 | 3 | | They generally move like an orthodox queen, |
2eef6db6 | 4 | | but capturing rules are complex. |
32cfcea4 BA |
5 | |
6 | h3 Specifications | |
7 | ||
8 | ul | |
9 | li Chessboard: standard. | |
10 | li Material: "standard". | |
11 | li Non-capturing moves: often like queen. | |
12 | li Special moves: none. | |
13 | li Captures: very special. | |
2f3c8451 | 14 | li End of game: standard; see below. |
32cfcea4 | 15 | |
15c1295a BA |
16 | h4 Pieces names |
17 | ||
18 | p Pieces names refer to the way they capture, which is described later. | |
19 | ul | |
20 | li Pawn : pawn or pincer | |
21 | li Rook : coordinator | |
22 | li Knight : long leaper | |
23 | li Bishop : chameleon | |
24 | li Queen : withdrawer | |
25 | li King : king (same behavior as in standard chess) | |
26 | p. | |
27 | Besides, a new piece is introduced: the immobilizer, represented by the letter 'm' | |
28 | in FEN diagrams and PGN games. It is represented by an upside-down rook: | |
29 | ||
30 | figure.diagram-container | |
31 | .diagram | |
32 | | fen:8/8/4m3/8/8/8/3M4/8: | |
33 | figcaption Immobilizers on d2 and e6. | |
34 | ||
32cfcea4 BA |
35 | h3 Non-capturing moves |
36 | ||
15c1295a BA |
37 | p |
38 | | Pawns move as orthodox rooks, and the king moves as usual, | |
39 | | one square in any direction. | |
40 | | All other pieces move like an orthodox queen. | |
41 | ||
42 | p When a piece is adjacent to an enemy immobilizer, it cannot move unless | |
43 | ul | |
44 | li it is an immobilizer or a chameleon; or | |
45 | li. | |
46 | the enemy immobilizer is adjacent to a friendly immobilizer or chameleon | |
47 | (cancelling the powers of the opponent's immobilizer) | |
48 | p | |
49 | | Note : this corresponds to the "pure rules" described on | |
50 | a(href="http://www.inference.org.uk/mackay/ultima/ultima.html") this page | |
51 | | , which slightly differ from the initial rules. | |
52 | | The aim is to get rid of the weird suicide rule, weakening the immobilizers lock | |
53 | | (in particular, in the original rules two adjacent immobilizer are stuck forever | |
54 | | until one is captured). | |
32cfcea4 BA |
55 | |
56 | h3 Capturing moves | |
57 | ||
15c1295a BA |
58 | p |
59 | | Easy case first: the king captures as usual, by moving onto an adjacent square | |
60 | | occupied by an enemy piece. But this is the only piece following orthodox rules, | |
61 | | and also the only one which captures by moving onto an occupied square. | |
62 | | All other pieces capture passively: they land on a free square and captured | |
63 | | units are determined by some characteristics of the movement. | |
64 | ||
65 | p Note: the immobilizer does not capture. | |
66 | ||
67 | h4 Pawns/Pincers | |
68 | ||
69 | p. | |
70 | If at the end of its movement a pawn is horizontally or vertically adjacent to an | |
71 | enemy piece, which itself is next to a friendly piece (in the same direction), | |
72 | the "pinced" unit is removed from the board. | |
73 | ||
74 | figure.diagram-container | |
75 | .diagram | |
76 | | fen:7k/5ppp/2N5/2n5/3rB3/8/PPP5/K7: | |
77 | figcaption 1.Pc2c4 captures both coordinator and long leaper. | |
78 | ||
79 | h4 Coordinators (rooks) | |
80 | ||
81 | p. | |
82 | Imagine that rook and king are two corners of a rectangle (this works if these | |
83 | two pieces are unaligned). | |
84 | If at the end of a rook move an enemy piece stands in any of the two remaining | |
85 | corners, it is captured. | |
86 | ||
87 | figure.diagram-container | |
88 | .diagram | |
89 | | fen:8/2b4K/2q5/3p1N1p/8/8/2R5/k7: | |
90 | figcaption 1.Rc5 captures on c7 and h5. | |
91 | ||
92 | h4 Long leapers (knights) | |
93 | ||
94 | p. | |
95 | A knight captures exactly as a queen in draughts game: by jumping over its enemies, | |
96 | as many times as it can/want but always in the same direction. | |
97 | In this respect it is less powerful than a draughts' queen: | |
98 | on the following diagram c8 or f6 cannot be captured. | |
99 | ||
100 | figure.diagram-container | |
101 | .diagram | |
102 | | fen:2n2b1k/3r4/8/3p4/8/3b4/3N4/K7 w d4,d6,d8: | |
103 | figcaption All marked squares are playable from d2. | |
104 | ||
105 | h4 Withdrawer (queen) | |
106 | ||
107 | p. | |
108 | The queen captures by moving away from an adjacent enemy piece, in the opposite | |
109 | direction (only the long leaper can jump). | |
110 | ||
111 | figure.diagram-container | |
112 | .diagram | |
113 | | fen:7k/8/8/3Qr3/8/8/8/K7 w a5,b5,c5: | |
114 | figcaption 1.Qa5, 1.Qb5 or 1.Qc5 captures the black rook. | |
115 | ||
116 | h4 Chameleon (bishop) | |
117 | ||
118 | p The chameleon captures pieces in the way they would capture. So, it | |
119 | ul | |
120 | li pinces pawns, | |
121 | li withdraws from withdrawers, | |
122 | li leaps over long leapers, | |
123 | li coordinates coordinators. | |
124 | p ...and these captures can be combined. | |
125 | ||
126 | figure.diagram-container | |
127 | .diagram | |
128 | | fen:7k/8/8/m3pP2/2n5/8/B7/K7 w a5,c4,e5: | |
129 | figcaption 1.Bd5 captures all marked pieces. | |
130 | ||
131 | p. | |
132 | Besides, chameleon immobilizes immobilizers (but cannot capture them since they | |
133 | do not capture). | |
134 | ||
135 | p. | |
136 | A chameleon captures the king in the same way the king captures, which means that | |
137 | a chameleon adjacent to a king gives check. | |
32cfcea4 BA |
138 | |
139 | h3 End of the game | |
140 | ||
15c1295a BA |
141 | p. |
142 | Checkmate or stalemate as in standard chess. Note however that checks are more | |
143 | difficult to see, because of the exotic capturing rules. For example, on the | |
144 | following diagram the white king cannot move to the marked squares because then | |
145 | the black pawn could capture by moving next to it. | |
146 | ||
147 | figure.diagram-container | |
148 | .diagram | |
149 | | fen:7k/8/8/p4r/4K3/8/8/8 w e5: | |
150 | figcaption 1.Ke5 is impossible | |
32cfcea4 BA |
151 | |
152 | h3 Credits | |
153 | ||
154 | p. | |
155 | A good starting point is the | |
156 | #[a(href="https://en.wikipedia.org/wiki/Baroque_chess") Wikipedia page], | |
157 | which also gives pointers to other interesting pages (including chessvariants.com, | |
158 | as usual). |