How to solve retro chess puzzles

You do not need to be a strong player to solve retro puzzles. You need to be a careful detective. This is the method that works best on Three Moves Ago.

1. Compare the two positions square by square

Write down what is different between the start and the target: which pieces moved, which squares are now empty, which are newly occupied. Each side has exactly three moves, so this list is your budget.

2. Account for every missing piece

A piece that disappeared was captured. Ask which enemy piece could have reached that square, and on which move. Captures by pawns are the easiest to spot, because the pawn ends up on a new file.

3. Count the moves you can see

If White clearly needs two moves for the visible changes, there is one move left to explain. Missing moves usually hide in one of three places: a piece that went out and came back, a capture made by a piece that then moved on, or a piece that took a longer route than you expected.

4. Look for checks and forced replies

If a king has moved, ask why. A check is often the reason, and it tells you the order: the check came first, and the king move was the reply.

5. Play it out and read the colours

Enter your six moves. Each move gets a colour:

Yellow tiles are the most useful clue. They mean you found a real move but the order is wrong, which is usually about checks or about which piece had to move first.

6. Save the hint for the hard part

You get one hint per case. It reveals the first move of the solution that you have not yet got right, so it is most valuable after an attempt or two, once you know which part of the story you are missing.

Common traps

• Thinking a piece on its home square never moved.
• Assuming the piece standing on a square is the one that made the capture there.
• Playing sensible chess moves. The solution often contains moves no player would choose.