A minor piece or pawn is overloaded or under-defended on a contested central or passed-pawn square.
SAE concept sae_25977 fires when a minor piece or pawn is overloaded or under-defended on a contested central or passed-pawn square.. It appears in 15 of 9,950 Climbchess puzzles (0.2%), spanning ELO 870–2400 (median 1460).
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This page documents A minor piece or pawn is overloaded or…, 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 minor piece or pawn is overloaded or under-defended on a contested central or passed-pawn square.
This pattern fires in 15 of our 9,950 tagged puzzles. The puzzles where it appears span ELO 870 to 2400, with a median rating of 1460. That distribution tells you whether this is a beginner cue or a master-level subtlety.
Pattern statistics
| Concept ID | sae_25977 |
|---|---|
| Puzzles where it fires | 15 |
| Min ELO | 870 |
| Median ELO | 1460 |
| Max ELO | 2400 |
| Coverage | 0.15% 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 h1QHG — ELO 870, themes: advancedPawn, crushing, discoveredAttack, side to move: White
- Puzzle h1QHG_F — ELO 870, themes: advancedPawn, crushing, discoveredAttack, side to move: Black
- Puzzle zuHxz — ELO 898, themes: deflection, endgame, mate, side to move: Black
- Puzzle zuHxz_F — ELO 898, themes: deflection, endgame, mate, side to move: White
- Puzzle zx1EE — ELO 1460, themes: crushing, defensiveMove, endgame, side to move: Black
- Puzzle zx1EE_F — ELO 1460, themes: crushing, defensiveMove, endgame, side to move: White
- Puzzle 00XbN — ELO 2093, themes: advancedPawn, advantage, endgame, side to move: Black
- Puzzle 00XbN_F — ELO 2093, themes: advancedPawn, advantage, endgame, side to move: White
- Puzzle AZkjs — ELO 2400, themes: backRankMate, endgame, mate, side to move: White
- Puzzle AZkjs_F — ELO 2400, themes: backRankMate, endgame, mate, side to move: Black
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_25977?
A minor piece or pawn is overloaded or under-defended on a contested central or passed-pawn square. 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 15 tagged puzzles (0.2% of the set), spanning Lichess ELO 870 to 2400 with a median of 1460.
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.