1. e2e4  1... e7e5  2. g1f3  2... b8c6  3. f1b5  3... a7a6  4. b5a4  4... g8f6  5. d2d3  5... f8c5  6. c2c3  6... b7b5  7. a4b3  7... d7d6  8. c1g5 This is a treacherous move. White invites the opponent to play the classic plan with h6-g5, leading to a sharp position. 8... h7h6  9. g5h4  9... c8d7 A rare choice. Two of the best chess players in the world decided to move the dark-squared bishop in this position, but they played it on different squares.