Fortress Xiangqi: twenty engine games

Companion study to the Fortress Xiangqi rules article: the twenty engine self-play games the article’s sample game was chosen from, in full. Fairy-Stockfish on both sides with opening sampling and anti-repetition steering, so the reserve actually gets used. Chapter one is the game the article embeds. Article: /rules/fortress-xiangqi

20 chapters

1. Game 1: Black mates on move 43 (the article’s game)86 moves

   The game the rules article embeds. Both new rules are visible: three soldiers cross the river and gain the sideways step, and Red drops its captured Treasure back on d1 because its own half is the only half it may enter. 17 drops (Red 10, Black 7). Black mates on move 43 with the…

2. Game 2: Red mates on move 84167 moves

   Red held the edge before the break, peaking at 634. The engine eval stayed inside a pawn of level through ply 99 of 167. The position broke open on ply 100. 54 drops (Red 28, Black 26). Red mates with the drop R@f8.

3. Game 3: Red mates on move 105209 moves

   Red held the edge before the break, peaking at 406. The engine eval stayed inside a pawn of level through ply 121 of 209. The position broke open on ply 122. 53 drops (Red 28, Black 25). Red mates with e6–d6.

4. Game 4: Red mates on move 117233 moves

   Black held the edge before the break, peaking at -576. The engine eval stayed inside a pawn of level through ply 169 of 233. The position broke open on ply 170. 52 drops (Red 26, Black 26). Red mates with f5–f6.

5. Game 5: Red mates on move 75149 moves

   Red held the edge before the break, peaking at 130. The engine eval stayed inside a pawn of level through ply 20 of 149. The position broke open on ply 21. 42 drops (Red 23, Black 19). Red mates with the drop P@d6.

6. Game 6: Black mates on move 75150 moves

   Black held the edge before the break, peaking at -230. The engine eval stayed inside a pawn of level through ply 74 of 150. The position broke open on ply 75. 42 drops (Red 23, Black 19). Black mates with b4–b3.

7. Game 7: Black mates on move 79158 moves

   Black held the edge before the break, peaking at -105. The engine eval stayed inside a pawn of level through ply 13 of 158. The position broke open on ply 14. 36 drops (Red 18, Black 18). Black mates with the drop P@b1.

8. Game 8: Black mates on move 63126 moves

   Black held the edge before the break, peaking at -230. The engine eval stayed inside a pawn of level through ply 44 of 126. The position broke open on ply 45. 34 drops (Red 16, Black 18). Black mates with the drop P@b1.

9. Game 9: Red mates on move 60119 moves

   Red held the edge before the break, peaking at 161. The engine eval stayed inside a pawn of level through ply 15 of 119. The position broke open on ply 16. 33 drops (Red 17, Black 16). Red mates with the drop P@d6.

10. Game 10: Red mates on move 53105 moves

    Red held the edge before the break, peaking at 0. The engine eval stayed inside a pawn of level through ply 3 of 105. The position broke open on ply 4. 27 drops (Red 14, Black 13). Red mates with the drop C@c7.

11. Game 11: Black mates on move 56112 moves

    Black held the edge before the break, peaking at -167. The engine eval stayed inside a pawn of level through ply 23 of 112. The position broke open on ply 24. 27 drops (Red 13, Black 14). Black mates with a3–a2.

12. Game 12: Black mates on move 51102 moves

    Red held the edge before the break, peaking at 0. The engine eval stayed inside a pawn of level through ply 4 of 102. The position broke open on ply 5. 25 drops (Red 12, Black 13). Black mates with the drop R@a1.

13. Game 13: Red mates on move 66131 moves

    Red held the edge before the break, peaking at 123. The engine eval stayed inside a pawn of level through ply 16 of 131. The position broke open on ply 17. 25 drops (Red 13, Black 12). Red mates with f7–f8.

14. Game 14: Red mates on move 4895 moves

    Red held the edge before the break, peaking at 0. The engine eval stayed inside a pawn of level through ply 3 of 95. The position broke open on ply 4. 23 drops (Red 13, Black 10). Red mates with e7–f7.

15. Game 15: Black mates on move 4896 moves

    Red held the edge before the break, peaking at 346. The engine eval stayed inside a pawn of level through ply 41 of 96. The position broke open on ply 42. 23 drops (Red 11, Black 12). Black mates with the drop P@b1.

16. Game 16: Red mates on move 4997 moves

    Red held the edge before the break, peaking at 188. The engine eval stayed inside a pawn of level through ply 7 of 97. The position broke open on ply 8. 23 drops (Red 12, Black 11). Red mates with the drop P@g6.

17. Game 17: Black mates on move 3876 moves

    Red held the edge before the break, peaking at 0. The engine eval stayed inside a pawn of level through ply 3 of 76. The position broke open on ply 4. 20 drops (Red 8, Black 12). Black mates with the drop P@a2.

18. Game 18: Black mates on move 4488 moves

    Black held the edge before the break, peaking at -113. The engine eval stayed inside a pawn of level through ply 6 of 88. The position broke open on ply 7. 20 drops (Red 8, Black 12). Black mates with the drop P@c1.

19. Game 19: Black mates on move 3876 moves

    Red held the edge before the break, peaking at 0. The engine eval stayed inside a pawn of level through ply 3 of 76. The position broke open on ply 4. 18 drops (Red 8, Black 10). Black mates with the drop P@b1.

20. Game 20: Red mates on move 3875 moves

    Formerly the article’s game, kept for the finish: Red mates with the cannon to e4, firing up the e-file over its own horse on e5 while the soldier on f5 covers the general’s last square. 19 drops (Red 11, Black 8). No soldier crosses the river in this one, which is why the articl…