Current position
Petrov's Defense: Three Knights Game
1.e4 e5 2.Nf3 Nf6
The Petrov's Defense starts with 1.e4 e5 2.Nf3 Nf6 and is catalogued under ECO C42, in the open games & french half of the book. The catalog indexes 50 lines inside it, grouped into 43 named variations, and the position after those moves has 1 playable continuation to walk from here.
Root edges show how often each move is played around your Elo. Use the arrow on a position to reveal the next replies.
Current setup
Move ideas
Claims the center with a pawn and opens lines for the queen and king’s bishop.
Idea: Build quick development and make early castling possible.
Meets White’s center directly and opens lines for Black’s queen and bishop.
Idea: Fight for equal central space in a balanced, open position.
Develops the king’s knight and attacks Black’s e5-pawn.
Idea: Increase central pressure while getting ready to castle.
Develops the knight to f6, bringing it into the game.
Idea: Improve piece coordination and clear the back rank for castling and the rooks.
Develops the knight to c3, bringing it into the game.
Idea: Improve piece coordination and clear the back rank for castling and the rooks.
Develops the knight to c6, bringing it into the game.
Idea: Improve piece coordination and clear the back rank for castling and the rooks.
Develops the bishop to b5, bringing it into the game.
Idea: Improve piece coordination and clear the back rank for castling and the rooks.
Develops the bishop to b4, bringing it into the game.
Idea: Improve piece coordination and clear the back rank for castling and the rooks.
Tucks the king away and activates the rook in a single move.
Idea: Finish kingside development so the central pieces can coordinate safely.
Tucks the king away and activates the rook in a single move.
Idea: Finish kingside development so the central pieces can coordinate safely.
Advances to d3 to claim central space and control nearby key squares.
Idea: Give the pieces room to develop behind a durable central foothold.
Advances to d6 to claim central space and control nearby key squares.
Idea: Give the pieces room to develop behind a durable central foothold.
Develops the bishop to g5, bringing it into the game.
Idea: Improve piece coordination and clear the back rank for castling and the rooks.
Waiting for Lichess game popularity.
Each line below is an indexed entry under Petrov's Defense. Open one to load it on the board and keep exploring from that position.
19 more named lines sit inside this family — the tree above walks all of them.
ECO groups openings by the structures they lead to, so these families tend to share plans with the Petrov's Defense.