A king on the back rank or 2nd rank under back-rank pressure, requiring an immediate defensive move.
SAE concept sae_9544 fires when a king on the back rank or 2nd rank under back-rank pressure, requiring an immediate defensive move.. It appears in 130 of 9,950 Climbchess puzzles (1.3%), spanning ELO 680–2690 (median 1571).
Free forever · no email · no signup · delete data anytime.
This page documents A king on the back rank or 2nd rank under…, one of 4,505 interpretable chess concepts extracted from Leela Chess Zero via sparse autoencoders. The full feature description from our SAE labelling pipeline reads:
A king on the back rank or 2nd rank under back-rank pressure, requiring an immediate defensive move.
This pattern fires in 130 of our 9,950 tagged puzzles. The puzzles where it appears span ELO 680 to 2690, with a median rating of 1571. That distribution tells you whether this is a beginner cue or a master-level subtlety.
Pattern statistics
| Concept ID | sae_9544 |
|---|---|
| Puzzles where it fires | 130 |
| Min ELO | 680 |
| Median ELO | 1571 |
| Max ELO | 2690 |
| Coverage | 1.31% of puzzle set |
Related concepts
The five concepts most often co-firing alongside this one (Jaccard similarity over the puzzle co-occurrence graph) are:
Example puzzles
Below are 10 puzzles spanning the rating distribution. Each links to its own page with full move list and related concepts.
- Puzzle zzwxG_M — ELO 680, themes: advantage, defensiveMove, endgame, side to move: Black
- Puzzle xEvUf — ELO 885, themes: crushing, defensiveMove, middlegame, side to move: Black
- Puzzle zipga — ELO 1081, themes: crushing, defensiveMove, endgame, side to move: White
- Puzzle zinr4_F — ELO 1183, themes: crushing, endgame, exposedKing, side to move: White
- Puzzle zs69b_M — ELO 1256, themes: crushing, endgame, hangingPiece, side to move: White
- Puzzle zwkCg — ELO 1571, themes: crushing, defensiveMove, middlegame, side to move: Black
- Puzzle zvwST_M — ELO 1673, themes: advantage, middlegame, quietMove, side to move: White
- Puzzle zu7IX — ELO 1938, themes: crushing, defensiveMove, middlegame, side to move: Black
- Puzzle zjbhj_M — ELO 2235, themes: crushing, defensiveMove, endgame, side to move: Black
- Puzzle zlumR_F — ELO 2596, themes: advantage, defensiveMove, middlegame, side to move: White
How to use this page
If you want to train this pattern, open the Climbchess trainer and filter for puzzles tagged with this concept. The trainer surfaces them at the right difficulty for your current rating, and tracks how often you spot the cue versus miss it. You can also browse the related concepts above to see neighbouring ideas in feature space.
Climbchess concepts are not heuristics written by a human author. Each one corresponds to a single direction in the residual stream of Leela Chess Zero that activates on a specific board feature, then was labelled by reading the top-activating positions. This makes the catalogue exhaustive (every Leela-detectable pattern is in here somewhere) and falsifiable (you can replay our extraction).
Frequently asked
What is SAE concept sae_9544?
A king on the back rank or 2nd rank under back-rank pressure, requiring an immediate defensive move. It is one of 4,505 interpretable features extracted from Leela Chess Zero's residual stream via sparse autoencoders, then labelled by reading the top-activating positions.
Where does this pattern appear?
In 130 tagged puzzles (1.3% of the set), spanning Lichess ELO 680 to 2690 with a median of 1571.
How do I train it?
Open the Climbchess trainer and filter for puzzles tagged with this concept. The trainer adapts difficulty using your live recognition profile and tracks how often you spot the cue versus miss it.
Is it free?
Yes. Climbchess is free forever, with no account, email, or signup required. You can delete your data at any time.