Chess Visualization with Aiden Rayner

🧠🧠 Fiantrio (Illegal Move Exercise)

February 13th, 2026

Illegal Move Exercise: The audio will lead you through a series of moves from the beginning of a game. Somewhere in there, a player will make an illegal move but the game will continue anyway. Find the illegal move.

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PGN for today's exercise:

  1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. Nxd4 Nf6 5. Nxc6 bxc6 6. e5 Qe7 7. Qe2 Nd5 8. c4 Ba6 9. b3 g6 10. Bb2 Bg7 11. g3 O-O-O 12. Bg2 d6 13. Bxc6 Nb4 14. Bg2 dxe5 15. 0-0 f5 16. Nd2 Rhe8 *

And the answer is...
White's move 13. Bxc6 is illegal because there is a black Knight on d5 blocking the Bishop's path.