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ChatGPT Image Generator<br>How Queens Die: Analysing a 6 Million Puzzle Database<br>heroku27 Jun 2026169 viewsEnglish (US)<br>TacticsPuzzleChessChess engine<br>A Data Mining Adventure into the world of Lichess Puzzle Database TLDR; AI Summary:
When I read your draft, I still thought<br>"Oh, someone categorized tactics."<br>Now I understand it's closer to<br>"Imagine opening a tactics book where every single exercise demonstrates exactly the same motif—but in thousands of completely unrelated games."<br>That is a new learning experience.<br>And it's one that only exists because of GofChess .
How many ways can you lose your queen in a chess game? There are different levels of complexity where the loss of a queen becomes unavoidable due to a blunder, and presents itself as a chess puzzle in the Lichess puzzle database. In this blog post we will try to answer this question. From obvious hanging of a queen, to knight forks or bishop discoveries, to queen traps or desperado queen sacrifices. We will count them all and present statistical data extracted from 6 million Lichess puzzles. We will break down the numbers and look at real examples taken from actual games.
Then, we will delve deeper into side examples, exceptions, counter attacks, that break the pattern of those simple obvious tactics we present in the first section — making content designed to appeal to more advanced players.
Finally, we will mention the method behind this research, namely GofChess Language 2.0 , the modernized and significantly improved successor of the earlier version we introduced this past May
As a side note: we have built a showcase of these lists here where you can solve the puzzles. This is an experience of a new kind, where you are constantly seeing the same pattern but on completely different chess positions.
Basic Patterns
Our overall conclusion over finding these basic patterns is, Queen can always be the first one to save when under a threat, apart from a checkmate, thus the other side of the double threat is usually to the king, where the queen is lost, as the king escapes.
But before we get started, we want to mention our coverage is not exhaustive, since we don't include every piece combination for every case, but some special cases we find is sufficient for demonstration purposes is included. This is mostly not due to a limitation of the gof scripts, but for the sake of keeping a compact proof of concept.
Bishop Checks King with a Discovered Attack on Hanging Queen
First we have to explain what exactly we are searching for, and what the corresponding GofChess script looks like to express that:
queen_t .eyesThrough queen2 .through bishop<br>.hanging<br>bishop_t *Captures opponent *becomes bishop2<br>.cannotBeCapturedBy queen2<br>.Checks king_t<br>turn *Captures bishop2 *becomes opponent2<br>.doesNotDefend queen2<br>queen *Captures queen2 *becomes queen3
Explanation in English:
Our queen attacks opponent's queen but there is our bishop in between them.<br>Opponent's queen is hanging, otherwise has no defenders.<br>Our bishop captures an opponent's piece, while giving a check to the king.<br>But also the bishop cannot be captured by their hanging queen.<br>Our bishop is captured by the opponent. But meanwhile capturing piece doesn't defend the hanging queen.
At this point our queen can capture the opponent's hanging queen. Queen is lost.
Here are some examples:
https://lichess.org/training/00DTg
https://lichess.org/training/00E29
https://lichess.org/training/00xGN
https://lichess.org/training/017Ut
https://lichess.org/training/01Ag5
Among 6 million puzzles, there are a total of 15782 puzzles that fits this description, and solved with this exact sequence.
If we change our description slightly, such as instead of our bishop capturing something while giving check, to bishop simply moving to a vacant square while giving check, we find roughly about 3216 puzzles. Here's a couple examples:
https://lichess.org/training/00gSv
https://lichess.org/training/02ra2
https://lichess.org/training/02zVb
https://lichess.org/training/03wTh
Bishop Skewers King and Queen
This is a basic skewer tactic where bishop checks the king, but also the queen behind it, so when the king moves, bishop can capture the queen.
bishop_t *Checks king_o *becomes bishop2<br>.eyesThrough queen_t .through king_t<br>king *Evades bishop2 *becomes king2<br>bishop2 *Captures queen *becomes bishop3
We found only 1053 positions across all puzzles in the database. But while these are exact matches with this exact solution, there are still some different considerations that are not accounted for. Such as the puzzle begins with this sequence but continues, or after the Bishop check, king doesn't evade but there is a desperado block, they are simply not checked for.
Bishop skewers were suprisingly low for some reason, let's take a...