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2   <title>Two Kings</title>
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9
10   <h1>Two Kings</h1>
11
12   <table cellpadding="20">
13     <tr>
14       <td><img src="TwoKings.png"></td>
15
16       <td>
17         <h3>Initial setup</h3>
18
19         <p>e1, e8, f1, f8: King<br>
20         d1, d8: Queen<br>
21         a1, a8, h1, h8: Rook<br>
22         c1, c8: Bishop<br>
23         b1, b8, g1, g8: Knight<br>
24         a2-h2, a7-h7: Pawns</p>
25       </td>
26     </tr>
27   </table>
28
29   <h3>Moves at a Glance</h3>
30
31   <p>Click on a piece below to see its moves</p>
32
33   <table class="board">
34     <tr>
35       <td class="h" id="sq0x9"></td>
36
37       <td class="n" id="sq1x9" onmousedown="down_click(1,-9)"
38       onmouseup="up_click()"><img src="sym/BlackRook.png"></td>
39
40       <td class="n" id="sq2x9"></td>
41
42       <td class="n" id="sq3x9"></td>
43
44       <td class="n" id="sq4x9"></td>
45
46       <td class="n" id="sq5x9" onmousedown="down_click(5,9)"
47       onmouseup="up_click()"><img src="sym/BlackKing.png"></td>
48
49       <td class="n" id="sq6x9"></td>
50
51       <td class="n" id="sq7x9"></td>
52
53       <td class="n" id="sq8x9" onmousedown="down_click(8,9)"
54       onmouseup="up_click()"><img src="sym/BlackRook.png"></td>
55
56       <td class="h" id="sq9x9"></td>
57
58       <td class="h"><img src="sym/yellow.png"></td>
59
60       <td class="w" rowspan="2" valign="top">
61         <p>Sliding capture or non-capture,<br>
62         can be blocked on any square along the ray</p>
63       </td>
64     </tr>
65
66     <tr>
67       <td class="h" id="sq0x8"></td>
68
69       <td class="n" id="sq1x8"></td>
70
71       <td class="n" id="sq2x8"></td>
72
73       <td class="n" id="sq3x8"></td>
74
75       <td class="n" id="sq4x8"></td>
76
77       <td class="n" id="sq5x8"></td>
78
79       <td class="n" id="sq6x8"></td>
80
81       <td class="n" id="sq7x8"></td>
82
83       <td class="n" id="sq8x8"></td>
84
85       <td class="h" id="sq9x8"></td>
86     </tr>
87
88     <tr>
89       <td class="h" id="sq0x7"></td>
90
91       <td class="n" id="sq1x7"></td>
92
93       <td class="n" id="sq2x7"></td>
94
95       <td class="n" id="sq3x7"></td>
96
97       <td class="n" id="sq4x7"></td>
98
99       <td class="n" id="sq5x7"></td>
100
101       <td class="n" id="sq6x7"></td>
102
103       <td class="n" id="sq7x7"></td>
104
105       <td class="n" id="sq8x7"></td>
106
107       <td class="h" id="sq9x7"></td>
108
109       <td class="h"><img src="sym/orange.png"></td>
110
111       <td class="w">Unblockable leap (capture or non-capture)</td>
112     </tr>
113
114     <tr>
115       <td class="h" id="sq0x6"></td>
116
117       <td class="n" id="sq1x6"></td>
118
119       <td class="n" id="sq2x6"></td>
120
121       <td class="n" id="sq3x6"></td>
122
123       <td class="n" id="sq4x6"></td>
124
125       <td class="n" id="sq5x6"></td>
126
127       <td class="n" id="sq6x6"></td>
128
129       <td class="n" id="sq7x6"></td>
130
131       <td class="n" id="sq8x6"></td>
132
133       <td class="h" id="sq9x6"></td>
134
135       <td class="h"><img src="sym/green.png"></td>
136
137       <td class="w">Non-capture only</td>
138     </tr>
139
140     <tr>
141       <td class="h" id="sq0x5"></td>
142
143       <td class="n" id="sq1x5"></td>
144
145       <td class="n" id="sq2x5"></td>
146
147       <td class="n" id="sq3x5"></td>
148
149       <td class="n" id="sq4x5"></td>
150
151       <td class="n" id="sq5x5"></td>
152
153       <td class="n" id="sq6x5"></td>
154
155       <td class="n" id="sq7x5"></td>
156
157       <td class="n" id="sq8x5"></td>
158
159       <td class="h" id="sq9x5"></td>
160
161       <td class="h"><img src="sym/red.png"></td>
162
163       <td class="w">Capture only</td>
164     </tr>
165
166     <tr>
167       <td class="h" id="sq0x4"></td>
168
169       <td class="n" id="sq1x4"></td>
170
171       <td class="n" id="sq2x4"></td>
172
173       <td class="n" id="sq3x4"></td>
174
175       <td class="n" id="sq4x4"></td>
176
177       <td class="n" id="sq5x4"></td>
178
179       <td class="n" id="sq6x4"></td>
180
181       <td class="n" id="sq7x4"></td>
182
183       <td class="n" id="sq8x4"></td>
184
185       <td class="h" id="sq9x4"></td>
186     </tr>
187
188     <tr>
189       <td class="h" id="sq0x3"></td>
190
191       <td class="n" id="sq1x3" onmousedown="down_click(1,3)"
192       onmouseup="up_click()"><img src="sym/BlackPawn.png"></td>
193
194       <td class="n" id="sq2x3" onmousedown="down_click(2,3)"
195       onmouseup="up_click()"><img src="sym/WhitePawn.png"></td>
196
197       <td class="n" id="sq3x3" onmousedown="down_click(3,3)"
198       onmouseup="up_click()"><img src="sym/WhiteRook.png"></td>
199
200       <td class="n" id="sq4x3" onmousedown="down_click(4,3)"
201       onmouseup="up_click()"><img src="sym/WhiteKnight.png"></td>
202
203       <td class="n" id="sq5x3" onmousedown="down_click(5,3)"
204       onmouseup="up_click()"><img src="sym/WhiteQueen.png"></td>
205
206       <td class="n" id="sq6x3" onmousedown="down_click(6,3)"
207       onmouseup="up_click()"><img src="sym/WhiteBishop.png"></td>
208
209       <td class="n" id="sq7x3" onmousedown="down_click(7,3)"
210       onmouseup="up_click()"><img src="sym/WhiteKing.png"></td>
211
212       <td class="n" id="sq8x3"></td>
213
214       <td class="h" id="sq9x3"></td>
215     </tr>
216
217     <tr>
218       <td class="h" id="sq0x2"></td>
219
220       <td class="n" id="sq1x2"></td>
221
222       <td class="n" id="sq2x2"></td>
223
224       <td class="n" id="sq3x2"></td>
225
226       <td class="n" id="sq4x2"></td>
227
228       <td class="n" id="sq5x2"></td>
229
230       <td class="n" id="sq6x2"></td>
231
232       <td class="n" id="sq7x2"></td>
233
234       <td class="n" id="sq8x2"></td>
235
236       <td class="h" id="sq9x2"></td>
237     </tr>
238
239     <tr>
240       <td class="h" id="sq0x1"></td>
241
242       <td class="n" id="sq1x1"></td>
243
244       <td class="n" id="sq2x1" onmousedown="down_click(-2,1)"
245       onmouseup="up_click()"><img src="sym/WhitePawn.png"></td>
246
247       <td class="n" id="sq3x1"></td>
248
249       <td class="n" id="sq4x1"></td>
250
251       <td class="n" id="sq5x1"></td>
252
253       <td class="n" id="sq6x1"></td>
254
255       <td class="n" id="sq7x1"></td>
256
257       <td class="n" id="sq8x1"></td>
258
259       <td class="h" id="sq9x1"></td>
260     </tr>
261
262     <tr>
263       <td class="h" id="sq0x0"></td>
264
265       <td class="n" id="sq1x0"></td>
266
267       <td class="n" id="sq2x0"></td>
268
269       <td class="n" id="sq3x0"></td>
270
271       <td class="n" id="sq4x0"></td>
272
273       <td class="n" id="sq5x0"></td>
274
275       <td class="n" id="sq6x0"></td>
276
277       <td class="n" id="sq7x0"></td>
278
279       <td class="n" id="sq8x0"></td>
280
281       <td class="h" id="sq9x0"></td>
282     </tr>
283   </table>
284
285   <p id="piece" height="20">:<br>
286   :<br>
287   :<br>
288   :</p>
289
290   <table cellpadding="5" border="1">
291     <tr>
292       <td>Piece</td>
293
294       <td>ID</td>
295
296       <td>value</td>
297
298       <td>Moves (<a href="Betza.html">Betza notation</a>)</td>
299
300       <td>Remarks</td>
301     </tr>
302
303     <tr>
304       <td>King</td>
305
306       <td>K</td>
307
308       <td>-</td>
309
310       <td>K</td>
311
312       <td>Can castle with Rook, moving 2 steps towards it</td>
313     </tr>
314
315     <tr>
316       <td>Queen</td>
317
318       <td>Q</td>
319
320       <td>9.5</td>
321
322       <td>RB or Q</td>
323
324       <td></td>
325     </tr>
326
327     <tr>
328       <td>Rook</td>
329
330       <td>R</td>
331
332       <td>5</td>
333
334       <td>R</td>
335
336       <td></td>
337     </tr>
338
339     <tr>
340       <td>Bishop</td>
341
342       <td>B</td>
343
344       <td>3.25</td>
345
346       <td>B</td>
347
348       <td>Color-bound</td>
349     </tr>
350
351     <tr>
352       <td>Knight</td>
353
354       <td>N</td>
355
356       <td>3.25</td>
357
358       <td>N</td>
359
360       <td></td>
361     </tr>
362
363     <tr>
364       <td>Pawn</td>
365
366       <td>P</td>
367
368       <td>1</td>
369
370       <td>mfWcfF</td>
371
372       <td>Promotes to Q, R, B, or N on reaching last rank</td>
373     </tr>
374   </table>
375
376   <h3>Pawn peculiarities</h3>
377
378   <ul>
379     <li>Pawns capture differently from how they move (straight
380     move, diagonal capture).</li>
381
382     <li>Pawns can move two squares straight ahead from their
383     initial position, provided they are not blocked.</li>
384
385     <li>On the move immediately after such a double push, they can
386     be captured en passant by another Pawn, as if they had only
387     moved 1 square ahead.</li>
388
389     <li>Pawns promote to another (non-royal) piece of choice when
390     they reach last rank.</li>
391   </ul>
392
393   <h3>Castling</h3>
394
395   <p>An e-file King that has not moved before can move two squares
396   in the direction of a Rook that has not moved before, in which
397   case that Rook is moved to the square the King skipped over. This
398   is only allowed if all squares between King and Rook are empty,
399   when the King is not in check on the square it came from, and
400   would not be in check on any of the squares it skipped over.</p>
401
402   <h3>General rules</h3>
403
404   <ul>
405     <li>The King closest to square a1 is the royal one (horizontal
406     measure prevailing over vertical).</li>
407
408     <li>It is not allowed to expose your <b>royal</b> King to
409     capture ('check').</li>
410
411     <li>The game is won by checkmating the opponent (i.e. being in
412     check, and not being able to get out of it).</li>
413
414     <li>Stalemate (no legal moves, but not in check) is a
415     draw.</li>
416   </ul>
417
418   <h3>Differences with FIDE</h3>
419
420   <p>You have a pair of Kings, and only a single Bishop. Only one
421   of the Kings is royal, but which one can change during the game,
422   as it depends on their relative location on the board.</p>
423
424   <h3>Strategy issues</h3>
425
426   <p>It is not possible to force checkmate on a bare King with just
427   a single Bishop or Knight (in addition to your own King). Two
428   Knights cannot do that either. Two Kings can force checkmate on a
429   bare King.</p>Your non-royal King can be exposed to capture, and
430   thus captured. After that, the remaining King will always be
431   royal. Once both sides are down to a single King, this variant
432   degenerate to orthodox Chess. The spare King is a tough defender,
433   because it cannot be attacked by the opponent's royal King. So if
434   all the attacker's power is in a single piece, the defending King
435   pair has little to fear when they protect each other. This makes
436   even KQKK is a draw (provided the Kings can connect).
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