A rare move that has been played by Keymer before.
1. d2d4  1... g8f6  2. c2c4  2... e7e6  3. b1c3  3... d7d5  4. c4d5  4... e6d5  5. c1g5  5... f8b4 Another recent opening trend, spicing the game a bit compared to the more solid 5...Be7. 6. e2e3  6... h7h6 