Chess Variants/Fischer Random Chess

Introduction
Fischer Random Chess (also known as Chess960) is probably one of the best-known chess variants out there. Randomising the starting positions of the home-rank pieces eliminates the usage of opening theory and forces players to use skill and creativity to gain an advantage over their opponent.

Fischer Random Chess also had its rules implemented into the FIDE Laws of Chess in 2008, the only chess variant with this honour.

History
Although chess variants with randomised opening setups had been suggested as early as 1792, Fischer Random itself was created by its namesake, former Chess Champion Bobby Fischer, who began developing the rules after his 1992 match with Boris Spassky. The rules were formulated in 1993 and unveiled formally to the chess world on June 19, 1996, in Buenos Aires, Argentina. The first Fischer Random tournament was held in Vojvodina, Yugoslavia in 1996.

Fischer's goal was to eliminate the usage of opening theory, forcing the players to use new and original strategies to gain the upper hand in the battle.

As you might guess, the name "Fischer Random Chess" is derived from Fischer's name. The alternate name "Chess960" was proposed by German chess player Hans-Walter Schmitt and is derived from the number of starting positions.

Rules
Fischer Random Chess is played in the same manner as the standard game, with the exception of the starting setup and castling.

Before a game of Fischer Random Chess begins, the starting position is determined and set up on the board. To begin, White's pieces (except his pawns) are placed in a random manner on the first rank, subject to two restrictions:


 * The two bishops must be on opposite colour squares.
 * The king must start somewhere in between the two rooks.

After the white pieces have been set up, the black pieces are placed equal-and-opposite to the white pieces (For example, if the white king is randomly determined to start on f1, the black king starts on f8).

Then, the pawns are set up as normal on the second and seventh ranks, and the game begins.

A modification is also made to the rules concerning castling, in order to accommodate the random setup. Like in standard chess a player may castle one per game, moving both their king and rook in one move. Castling in Fischer Random works as follows:

A player may either castle a-side (the equivalent of queenside castling in standard chess) or h-side (the equivalent of kingside castling in standard chess).


 * When a player castles a-side, the king and rook are moved to the positions they would end on when castling queenside in standard chess (so, the king moves to c1 and the rook to d1).


 * When a player castles h-side, the king and rook are moved to the positions they would end on when castling kingside in standard chess (so, the king moves to g1 and the rook to f1).

Like in standard chess, in Fischer Random Chess there are a few restrictions concerning castling:


 * Neither the king nor the rook taking part in castling may have been previously moved in the game.
 * None of the squares in between the king's starting square and destination square may be under attack by an enemy piece.
 * The king may not be in check.
 * All of the squares in between the king's starting and destination squares must be clear of pieces, with the exception of the rook taking part in castling.

Sometimes these castling rules can create interesting situations. For example, in the example diagrams shown here, the white rook on f1 does not move when White castles h-side. Also, if the black king started on c8 rather than b8, it would not move when castling.

Sub-variants

 * Chess480 uses a different castling rule - the king moves two squares towards the rook, and then the rook jumps to the other side of the king. As a result, castling cannot be done in a certain direction if the king does not have enough room to move (e.g. it starts on b1 or g1).
 * Shuffle chess does not use the starting setup restrictions, so bishops can be on the same colour squares and the king can be outside the two rooks. Castling cannot be done unless the king and rook are on their traditional starting squares
 * Chess256 (also known as Randompawns chess) applies the randomisation of Fischer Random Chess to the pawns, so each pawn will start on either the second or third rank. Only the pawns on the second rank are allowed the initial two-step move. Like in Fischer Random, Black's setup mirrors White's.

Example game
Event: FIDE World Fischer Random Championship

Site: Høvikodden, Akershus County, Norway

Date: October 31, 2019

Round: 1

White: Magnus Carlsen

Black: Wesley So

Starting position: QNBRKBRN

1. c4 e6 2. Nc3 d5 3. d4 dxc4 4. e3 a6 5. a4 b6 6. Bxc4 Bb7 7. Qb1 Ng6 8. e4 Bb4 9. Ng3 c5 10. d5 exd5 11. exd5 O-O 12. O-O Ne5 13. Ba2 c4 14. Qe4 Bxc3 15. bxc3 Rfe8 16. Bxc4 Nbd7 17. Nf5 Nf6 18. Qh4 Bxd5 19. Bxd5 Rxd5 20. Rxd5 Nxd5 21. Nxg7 Kxg7 22. c4 Re6 23. Qg3+ Ng6 24. cxd5 Qxd5 25. h3 Re2 26. Be3 b5 27. Rc1 h5 28. axb5 axb5 29. Kh2 Qe5 30. Qxe5+ Nxe5 31. Rc5 Nd3 32. Rxh5 Nxf2 33. Bd4+ Kg6 34. Rxb5 Ne4 35. h4 f5 36. Kh3 Rd2 37. Rb6+ Kh5 38. Be3 Rd6 39. Rb5 Kg6 40. Rb3 Rd1 41. g3 Rh1+ 42. Kg2 Re1 43. Rb6+ Kf7 44. Bf4 Re2+ 45. Kf3 Rf2+ 46. Ke3 Ra2 47. Rb3 Nf6 48. Bb8 Ra6 49. Kf3 Kg6 50. Be5 Re6 51. Rb5 Ra6 52. Bb2 Nh5 53. Rb8 Ra5 54. Rg8+ Kf7 55. Rg5 Nf6 56. Kf4 Rb5 57. Be5 Ke6 58. Ba1 Ra5 59. Bxf6 Kxf6 60. Rg8 Ra4+ 61. Kf3 Ra3+ 62. Kg2 Ra2+ 63. Kh3 Ra1 64. Rb8 Ra2 65. Rb6+ Kg7 66. Rb4 Kg6 67. Rf4 Rb2 68. Rf1 Ra2 69. Rb1 Rc2 70. Rb6+ Kh5 71. Rf6 Rf2 72. Rf8 Kg6 73. Rg8+ Kf7 74. Ra8 Rb2 75. h5 Kg7 76. Ra6 Rb4 77. Rg6+ Kf7 78. Kg2 Rb2+ 79. Kh3 Rb4 80. Rc6 Kg7 81. Ra6 Rc4 82. h6+ Kh7 83. Rf6 Ra4 84. Kg2 Ra3 85. Rxf5 Kxh6 86. Rf3 Rxf3 87. Kxf3 Kg5 88. g4 Kg6 89. Kf4 Kf6 90. g5+ Kg6 91. Kg4 Kf7 92. Kf5 Kg7 93. g6 Kg8 94. Kf6 Kf8 95. g7+ Kg8 96. Kg6 1/2-1/2