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This page is written by the game's inventor, Steve Costa.

# (Sequence Chess)

### By Stephen D. Costa

This is something I have recently come up with. The number of variants possible is virtually infinite (see Variants section).

Fibonacci Chess is played on an 8x8 board just like regular chess, but the Fibonacci sequence details times when opponents SWITCH moves. Moves made with an opponents' pieces must be legal.

Fibonacci sequence: 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377...

So in a Fibonacci game, the player with the Black pieces makes White's first move; the player with the White pieces makes Black's first move. This "switch" happens again on move 2, and so forth. Any "switched" move must be played in the order it would be played in a normal game of chess.

The first ten moves, therefore, would be played as follows:

1. B W / 2. B W / 3. B W / 4. W B / 5. B W / 6. W B / 7. W B / 8. B W / 9. W B / 10. W B

VARIANTS

Variant #1 - One Switch: White and Black get to make each other's first move, but the rest of the game proceeds like normal chess.

Variant #2 - Double Trouble: White and Black "switch" on Move 1. Then black gets to move both White and Black move #2; White gets to move White and Black #3, and so forth. Each player then gets several chances to play three consecutive moves, likely resulting in fast games. Each move must be legal.

The first ten moves would be played as follows:

1. B W / 2. B B / 3. W W / 4. W B / 5. B B / 6. W B / 7. W B / 8. W W / 9. W B / 10. W B

Variant #3 - Different Sequences: White and Black can agree on any switch sequence and either style of switching off moves. For example, there could be switches every 5 moves, every 10 moves, every prime number; use your imagination!

Variant #4 - No Forced Captures -- If you move your opponent's pieces on move N, you may not capture them on move N+1 or any subsequent move N+M if all moves from move N through move N+M have given check to your opponent (this is to prevent a forced move of a powerful piece into an "obvious" capture).

Variant #5 - Forced Captures - If making an opponent's move, you MUST capture one of your own pieces if possible. If you cannot do so, you lose the ability to make that move for your opponent. For Variant 5a, you lose your turn and your opponent makes no move; for Variant 5b, your opponent gets to make his own move.

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