3 <title>Two Kings</title>
4 <link rel=StyleSheet href="./moves.css" type="text/css">
5 <script type="text/javascript" src="spartan.js"></script>
9 <table cellpadding="20"><tr><td>
10 <img src="TwoKings.png">
12 <h3>Initial setup</h3>
22 b1, b8, g1, g8: Knight
28 <h3>Moves at a Glance</h3>
30 <p>Click on a piece below to see its moves</p>
32 <table class="board"><tr><td class="h" id="0x9">
34 </td><td class="n" id="1x9" onmouseDown="down_click(1,-9)" onmouseUp="up_click()">
35 <img src="sym/BlackRook.png">
36 </td><td class="n" id="2x9">
38 </td><td class="n" id="3x9">
40 </td><td class="n" id="4x9">
42 </td><td class="n" id="5x9" onmouseDown="down_click(5,9)" onmouseUp="up_click()">
43 <img src="sym/BlackKing.png">
44 </td><td class="n" id="6x9">
46 </td><td class="n" id="7x9">
48 </td><td class="n" id="8x9" onmouseDown="down_click(8,9)" onmouseUp="up_click()">
49 <img src="sym/BlackRook.png">
50 </td><td class="h" id="9x9">
53 <img src="sym/yellow.png">
54 </td><td class="w" rowspan="2" valign="top">
55 <p>Sliding capture or non-capture,<br>can be blocked on any square along the ray</p>
56 </td></tr><tr><td class="h" id="0x8">
58 </td><td class="n" id="1x8">
60 </td><td class="n" id="2x8">
62 </td><td class="n" id="3x8">
64 </td><td class="n" id="4x8">
66 </td><td class="n" id="5x8">
68 </td><td class="n" id="6x8">
70 </td><td class="n" id="7x8">
72 </td><td class="n" id="8x8">
74 </td><td class="h" id="9x8">
76 </td></tr><tr><td class="h" id="0x7">
78 </td><td class="n" id="1x7">
80 </td><td class="n" id="2x7">
82 </td><td class="n" id="3x7">
84 </td><td class="n" id="4x7">
86 </td><td class="n" id="5x7">
88 </td><td class="n" id="6x7">
90 </td><td class="n" id="7x7">
92 </td><td class="n" id="8x7">
94 </td><td class="h" id="9x7">
97 <img src="sym/orange.png">
99 Unblockable leap (capture or non-capture)
100 </td></tr><tr><td class="h" id="0x6">
102 </td><td class="n" id="1x6">
104 </td><td class="n" id="2x6">
106 </td><td class="n" id="3x6">
108 </td><td class="n" id="4x6">
110 </td><td class="n" id="5x6">
112 </td><td class="n" id="6x6">
114 </td><td class="n" id="7x6">
116 </td><td class="n" id="8x6">
118 </td><td class="h" id="9x6">
121 <img src="sym/green.png">
124 </td></tr><tr><td class="h" id="0x5">
126 </td><td class="n" id="1x5">
128 </td><td class="n" id="2x5">
130 </td><td class="n" id="3x5">
132 </td><td class="n" id="4x5">
134 </td><td class="n" id="5x5">
136 </td><td class="n" id="6x5">
138 </td><td class="n" id="7x5">
140 </td><td class="n" id="8x5">
142 </td><td class="h" id="9x5">
145 <img src="sym/red.png">
148 </td></tr><tr><td class="h" id="0x4">
150 </td><td class="n" id="1x4">
152 </td><td class="n" id="2x4">
154 </td><td class="n" id="3x4">
156 </td><td class="n" id="4x4">
158 </td><td class="n" id="5x4">
160 </td><td class="n" id="6x4">
162 </td><td class="n" id="7x4">
164 </td><td class="n" id="8x4">
166 </td><td class="h" id="9x4">
168 </td></tr><tr><td class="h" id="0x3">
170 </td><td class="n" id="1x3" onmouseDown="down_click(1,3)" onmouseUp="up_click()">
171 <img src="sym/BlackPawn.png">
172 </td><td class="n" id="2x3" onmouseDown="down_click(2,3)" onmouseUp="up_click()">
173 <img src="sym/WhitePawn.png">
174 </td><td class="n" id="3x3" onmouseDown="down_click(3,3)" onmouseUp="up_click()">
175 <img src="sym/WhiteRook.png">
176 </td><td class="n" id="4x3" onmouseDown="down_click(4,3)" onmouseUp="up_click()">
177 <img src="sym/WhiteKnight.png">
178 </td><td class="n" id="5x3" onmouseDown="down_click(5,3)" onmouseUp="up_click()">
179 <img src="sym/WhiteQueen.png">
180 </td><td class="n" id="6x3" onmouseDown="down_click(6,3)" onmouseUp="up_click()">
181 <img src="sym/WhiteBishop.png">
182 </td><td class="n" id="7x3" onmouseDown="down_click(7,3)" onmouseUp="up_click()">
183 <img src="sym/WhiteKing.png">
184 </td><td class="n" id="8x3">
186 </td><td class="h" id="9x3">
188 </td></tr><tr><td class="h" id="0x2">
190 </td><td class="n" id="1x2">
192 </td><td class="n" id="2x2">
194 </td><td class="n" id="3x2">
196 </td><td class="n" id="4x2">
198 </td><td class="n" id="5x2">
200 </td><td class="n" id="6x2">
202 </td><td class="n" id="7x2">
204 </td><td class="n" id="8x2">
206 </td><td class="h" id="9x2">
208 </td></tr><tr><td class="h" id="0x1">
210 </td><td class="n" id="1x1">
212 </td><td class="n" id="2x1" onmouseDown="down_click(-2,1)" onmouseUp="up_click()">
213 <img src="sym/WhitePawn.png">
214 </td><td class="n" id="3x1">
216 </td><td class="n" id="4x1">
218 </td><td class="n" id="5x1">
220 </td><td class="n" id="6x1">
222 </td><td class="n" id="7x1">
224 </td><td class="n" id="8x1">
226 </td><td class="h" id="9x1">
228 </td></tr><tr><td class="h" id="0x0">
230 </td><td class="n" id="1x0">
232 </td><td class="n" id="2x0">
234 </td><td class="n" id="3x0">
236 </td><td class="n" id="4x0">
238 </td><td class="n" id="5x0">
240 </td><td class="n" id="6x0">
242 </td><td class="n" id="7x0">
244 </td><td class="n" id="8x0">
246 </td><td class="h" id="9x0">
250 <p id="piece" height="20">:<br>:<br>:<br>:</p>
252 <table cellpadding="5" border="1"><tr><td>
259 Moves (<a href="Betza.html">Betza notation</a>)
271 Can castle with Rook, moving 2 steps towards it
321 Promotes to Q, R, B, or N on reaching last rank
323 <h3>Pawn peculiarities</h3>
325 <li>Pawns capture differently from how they move (straight move, diagonal capture).</li>
326 <li>Pawns can move two squares straight ahead from their initial position, provided they are not blocked.</li>
327 <li>On the move immediately after such a double push, they can be captured en passant by another Pawn,
328 as if they had only moved 1 square ahead.</li>
329 <li>Pawns promote to another (non-royal) piece of choice when they reach last rank.</li>
333 An e-file King that has not moved before can move two squares in the direction of a Rook that has not moved before,
334 in which case that Rook is moved to the square the King skipped over.
335 This is only allowed if all squares between King and Rook are empty,
336 when the King is not in check on the square it came from,
337 and would not be in check on any of the squares it skipped over.
339 <h3>General rules</h3>
341 <li>The King closest to square a1 is the royal one (horizontal measure prevailing over vertical).</li>
342 <li>It is not allowed to expose your <b>royal</b> King to capture ('check').</li>
343 <li>The game is won by checkmating the opponent (i.e. being in check, and not being able to get out of it).</li>
344 <li>Stalemate (no legal moves, but not in check) is a draw.</li>
346 <h3>Differences with FIDE</h3>
348 You have a pair of Kings, and only a single Bishop.
349 Only one of the Kings is royal, but which one can change during the game, as it depends on their relative location on the board.
351 <h3>Strategy issues</h3>
353 It is not possible to force checkmate on a bare King with just a single Bishop or Knight (in addition to your own King).
354 Two Knights cannot do that either.
355 Two Kings can force checkmate on a bare King.
357 Your non-royal King can be exposed to capture, and thus captured.
358 After that, the remaining King will always be royal.
361 Once both sides are down to a single King, this variant degenerate to orthodox Chess.
364 The spare King is a tough defender, because it cannot be attacked by the opponent's royal King.
365 So if all the attacker's power is in a single piece, the defending King pair has little to fear when they protect each other.
366 This makes even KQKK is a draw (provided the Kings can connect).