1. e2e4  1... e7e5  2. g1f3  2... b8c6  3. f1c4  3... f8c5  4. c2c3  4... g8f6  5. d2d4  5... e5d4  6. b2b4 A very rare  move. And a top guess by Dubov as we shall witness! 6... c5b6  7. e4e5  7... f6e4 