Detects white king safely castled on the back rank (typically b1 or g1) in middlegame positions, surrounded by own pieces.
SAE concept sae_1449 fires when detects white king safely castled on the back rank (typically b1 or g1) in middlegame positions, surrounded by own pieces.. It appears in 4,511 of 9,950 Climbchess puzzles (45.3%), spanning ELO 626–2696 (median 1659).
Free forever · no email · no signup · delete data anytime.
This page documents Detects white king safely castled on the back…, 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 white king safely castled on the back rank (typically b1 or g1) in middlegame positions, surrounded by own pieces.
This pattern fires in 4,511 of our 9,950 tagged puzzles. The puzzles where it appears span ELO 626 to 2696, with a median rating of 1659. That distribution tells you whether this is a beginner cue or a master-level subtlety.
Pattern statistics
| Concept ID | sae_1449 |
|---|---|
| Puzzles where it fires | 4,511 |
| Min ELO | 626 |
| Median ELO | 1659 |
| Max ELO | 2696 |
| Coverage | 45.34% 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 zSBhc — ELO 626, themes: backRankMate, mate, mateIn2, side to move: Black
- Puzzle yzM5l_F — ELO 882, themes: endgame, exposedKing, long, side to move: Black
- Puzzle zz5Fz — ELO 1090, themes: advancedPawn, advantage, kingsideAttack, side to move: White
- Puzzle z7bOm_M — ELO 1307, themes: mate, mateIn2, middlegame, side to move: Black
- Puzzle 01m2g — ELO 1494, themes: crushing, endgame, short, side to move: White
- Puzzle 00SU7_M — ELO 1659, themes: advantage, fork, long, side to move: White
- Puzzle zv5sA_F — ELO 1854, themes: advancedPawn, attraction, crushing, side to move: White
- Puzzle DUTya_F — ELO 2073, themes: deflection, doubleBishopMate, kingsideAttack, side to move: White
- Puzzle j532K_M — ELO 2243, themes: attraction, hookMate, long, side to move: Black
- Puzzle ymyKz — ELO 2461, themes: advantage, middlegame, queensideAttack, 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_1449?
Detects white king safely castled on the back rank (typically b1 or g1) in middlegame positions, surrounded by own pieces. 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 4,511 tagged puzzles (45.3% of the set), spanning Lichess ELO 626 to 2696 with a median of 1659.
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.