Retro chess puzzle FAQ
What is Three Moves Ago?
A free daily chess puzzle. You see a target position and must find the three moves by White and the three moves by Black that led to it. You have five attempts and one hint, and every case has exactly one solution.
What is retrograde analysis in chess?
Retrograde analysis, or retro analysis, means reasoning backwards from a position to work out what happened earlier: which moves were played and which pieces were captured, and in what order. It was popularised by Raymond Smullyan’s book The Chess Mysteries of Sherlock Holmes.
What is a proof game?
A retro problem where you must find the game that reaches a given position in an exact number of moves. Every case here is a short proof game: three moves for each side.
What do Normal and Extreme mean?
Normal cases start from the usual opening position. Extreme · Midgame cases start from a real middlegame, after openings like the Italian or the Ruy Lopez, with many more pieces on the board.
What do the colours mean?
Green: right move at the right turn. Yellow: a move from the solution, played at the wrong turn. Grey: not part of the solution.
Do the moves have to be good chess moves?
No. They only have to be legal and lead to the exact position. Pieces may move and come back, and a missing piece means it was captured.
When does a new case come out?
Every day at 07:00 Romania time, at the same moment for every player. Past cases stay playable in the archive.