Chess Opening Theory/1. e4/1...e6/2. d4/2...d5/3. exd5/3...exd5/4. c4

=Monte Carlo Variation=

By playing 4.c4, White gains some space at the expense of not being able to defend the d-pawn. This move also tries to destabilize the d5 pawn, and open up a line for the bishop. c4 is also commonly played in other openings so it may be caused by habit as well.

Common responses by Black include Nf6 which guards the pawn and develops a knight, c6 also guarding the pawn, just taking the c4 pawn with dxc4, or Bb4+ to gain a tempo on the white king and develop a bishop.

Theory table
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