Detects squares on the 7th or 8th rank that are attacked by a black piece and not defended by a white piece, often in positions where white has a rook on the 8th rank.

By · · 3 min read · Updated May 8, 2026

SAE concept sae_40826 fires when detects squares on the 7th or 8th rank that are attacked by a black piece and not defended by a white piece, often in positions where white has a rook on the 8th rank.. It appears in 3 of 9,950 Climbchess puzzles (0.0%), spanning ELO 731–731 (median 731).

Free forever 4,505 patterns 9,950 puzzles 20 languages
Try Climbchess free — no signup, no email

Free forever · no email · no signup · delete data anytime.

This page documents Detects squares on the 7th or 8th rank that are…, 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 squares on the 7th or 8th rank that are attacked by a black piece and not defended by a white piece, often in positions where white has a rook on the 8th rank.

This pattern fires in 3 of our 9,950 tagged puzzles. The puzzles where it appears span ELO 731 to 731, with a median rating of 731. That distribution tells you whether this is a beginner cue or a master-level subtlety.

Pattern statistics

Concept IDsae_40826
Puzzles where it fires3
Min ELO731
Median ELO731
Max ELO731
Coverage0.03% 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 3 puzzles spanning the rating distribution. Each links to its own page with full move list and related concepts.

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_40826?

Detects squares on the 7th or 8th rank that are attacked by a black piece and not defended by a white piece, often in positions where white has a rook on the 8th rank. 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 3 tagged puzzles (0.0% of the set), spanning Lichess ELO 731 to 731 with a median of 731.

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.