1. e2e4  1... e7e5  2. g1f3  2... b8c6  3. f1b5  3... g8f6  4. d2d3  4... f8c5  5. e1g1 This is the least popular of the three main options, but there's still a lot of theory behind it. The problem is that it allows the exchange of knights. 5... c6d4 [%c_effect d4;square;d4;type;GreatFind;persistent;true] 6. f3d4  6... c5d4  7. c2c3  7... d4b6  8. b5a4 This is a prophylactic move that has been played by many strong GMs. White anticipates c7-c6.