1. c2c4  1... e7e6  2. b1c3  2... d7d5  3. d2d4  3... c7c6  4. e2e4 This variation is known as the \"Marshall Gambit.\" This is the only case of a player who has two excellent gambits named after him, one with White and one with Black. 4... d5e4  5. c3e4  5... f8b4  6. c1d2 The most critical move.