Detects mating net positions (swallow's tail, epaulette, Arabian) where black's defensive pieces are overloaded or misplaced.

By Climbchess Research · 2026-05-08 · 3 min read · Updated May 8, 2026

SAE concept sae_5587 fires when detects mating net positions (swallow's tail, epaulette, Arabian) where black's defensive pieces are overloaded or misplaced.. It appears in 34 of 9,950 Climbchess puzzles (0.3%), spanning ELO 621–2697 (median 1272).

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

This page documents Detects mating net positions (swallow's tail…, 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 mating net positions (swallow's tail, epaulette, Arabian) where black's defensive pieces are overloaded or misplaced.

This pattern fires in 34 of our 9,950 tagged puzzles. The puzzles where it appears span ELO 621 to 2697, with a median rating of 1272. That distribution tells you whether this is a beginner cue or a master-level subtlety.

Pattern statistics

Related concepts

The five concepts most often co-firing alongside this one (Jaccard similarity over the puzzle co-occurrence graph) are:

• A weakly defended square targeted by a tactical piece move, typically in a… — similarity 0.054
• Active black rook in an endgame, often on an open file or rank, participating… — similarity 0.033
• White Queen attacks a black pawn on the 7th rank, which is defended by at… — similarity 0.029
• Central tactical imbalance — an active piece under pressure where the attacker… — similarity 0.027
• A white rook attacks a black pawn on the 7th rank (commonly g7 or h7) that has… — similarity 0.020

Example puzzles

Below are 10 puzzles spanning the rating distribution. Each links to its own page with full move list and related concepts.

• Puzzle veb0b — ELO 621, themes: arabianMate, endgame, mate, side to move: Black
• Puzzle 02Ab5 — ELO 955, themes: endgame, mate, mateIn1, side to move: White
• Puzzle 00CtS_F — ELO 980, themes: endgame, mate, mateIn2, side to move: White
• Puzzle 01QId — ELO 1155, themes: endgame, epauletteMate, mate, side to move: White
• Puzzle zz6hu — ELO 1230, themes: advantage, deflection, endgame, side to move: White
• Puzzle zwBS0_F — ELO 1272, themes: advancedPawn, backRankMate, discoveredAttack, side to move: Black
• Puzzle v2kpd_M — ELO 1783, themes: arabianMate, discoveredAttack, discoveredCheck, side to move: White
• Puzzle zD1Ew_M — ELO 1809, themes: crushing, endgame, exposedKing, side to move: White
• Puzzle zqQ1T_M — ELO 2259, themes: crushing, discoveredAttack, discoveredCheck, side to move: Black
• Puzzle zjUt8_M — ELO 2261, themes: endgame, long, 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).