Detects kings in near-opposition or close proximity in simplified endgames (pawn, rook, or minor piece endings).
SAE concept sae_2631 fires when detects kings in near-opposition or close proximity in simplified endgames (pawn, rook, or minor piece endings).. It appears in 2,121 of 9,950 Climbchess puzzles (21.3%), spanning ELO 625–2698 (median 1623).
Free forever · no email · no signup · delete data anytime.
This page documents Detects kings in near-opposition or close…, 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:
Detects kings in near-opposition or close proximity in simplified endgames (pawn, rook, or minor piece endings).
This pattern fires in 2,121 of our 9,950 tagged puzzles. The puzzles where it appears span ELO 625 to 2698, with a median rating of 1623. That distribution tells you whether this is a beginner cue or a master-level subtlety.
Pattern statistics
| Concept ID | sae_2631 |
|---|---|
| Puzzles where it fires | 2,121 |
| Min ELO | 625 |
| Median ELO | 1623 |
| Max ELO | 2698 |
| Coverage | 21.32% 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 00aU5 — ELO 625, themes: crushing, endgame, master, side to move: Black
- Puzzle GkDwa_M — ELO 872, themes: advancedPawn, bishopEndgame, crushing, side to move: White
- Puzzle zvfu5 — ELO 1041, themes: advancedPawn, crushing, endgame, side to move: White
- Puzzle zv1cI_F — ELO 1202, themes: crushing, endgame, hangingPiece, side to move: White
- Puzzle zyCJZ — ELO 1404, themes: crushing, endgame, master, side to move: Black
- Puzzle zTqfb_M — ELO 1623, themes: advancedPawn, crushing, endgame, side to move: Black
- Puzzle zwxp4 — ELO 1817, themes: crushing, defensiveMove, endgame, side to move: Black
- Puzzle zHDHG — ELO 2024, themes: endgame, mate, mateIn1, side to move: White
- Puzzle ztqAG_F — ELO 2227, themes: attraction, capturingDefender, crushing, side to move: Black
- Puzzle m7oDG_M — ELO 2459, themes: endgame, mate, mateIn2, 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_2631?
Detects kings in near-opposition or close proximity in simplified endgames (pawn, rook, or minor piece endings). 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 2,121 tagged puzzles (21.3% of the set), spanning Lichess ELO 625 to 2698 with a median of 1623.
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.