Every position here is a real decision from a real grandmaster game in the Philidor Defense, taken at the ply where the game actually turned and checked against the engine before it reached you.
708 positions · 139 grandmasters
Play the Philidor DefenseA guided deck of 128, in your browser. Nothing to install, nothing to sign up for.
Each one is a game somebody actually played. Pick any of them.
We read the games grandmasters actually play and look for the ply where the game turned, rather than composing puzzles. The engine checks the answer before it reaches you, and the positions are ranked by how much they teach rather than how hard they are.
Every opening