Biggest Blunders in Classical (May 2025)

I have prepared ten diagrams featuring positions where very strong players made a serious mistake. Test yourself — take a moment to consider what move you would play in the position and think about why the move played in the game was a blunder. Some examples are simple, but others require some creativity, understanding and deeper calculation.
After you’ve made your choice, you can check it in this Lichess study, where each position is annotated with the full context, the move played in the game and why it failed.

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#10 Opposite-colored bishops (2593 rated player)

BLACK TO MOVE. What would you play?
What is wrong with gxh4?

#9 King in danger (2660 rated player)

BLACK TO MOVE. What would you play?
What is wrong with Ne5?

#8 Decoy (2457 rated player)

BLACK TO MOVE. What would you play?
What is wrong with Qg5?

#7 King ́s safety comes first (2573 rated player)

BLACK TO MOVE. What would you play?
What is wrong with e4?

#6 Coordination is the key (2520 rated player)

BLACK TO MOVE. What would you play?
What is wrong with Bd1?

#5 The game isn ́t over yet (2630 rated player)

WHITE TO MOVE. What would you play?
What is wrong with the continuation Rf7+ Ke8 Nb7?

#4 Watch your Queen (2564 rated player)

BLACK TO MOVE. What would you play?
What is wrong with Qe1?

#3 Queen trade: yes or no? (2455 rated player)

BLACK TO MOVE. What would you play?
What is wrong with Qc5?

#2 Be aware of zugzwang (2787 rated player)

BLACK TO MOVE. What would you play?
What is wrong with Bg5?

#1 Keep an eye on that pawn! (2668 rated player)

BLACK TO MOVE. What would you play?
What is wrong with Nxg3?