Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bc4/3...d6

=Paris Defence=

3... d6
Similar to the Philidor's Defence, but here the e5-pawn is already defended. Black's kingside bishop is now blocked in behind the pawn chain. White has a spatial advantage.

Theory table
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1.e4 e5 2.Nf3 Nc6 3.Bc4 d6