Puzzle zTimH — ELO 2059
This is a White-to-move puzzle rated 2059 ELO. The first move is d2d7, tagged with 10 interpretable concepts and Lichess themes: endgame, long, mate.
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Position
White to move. ELO 2059. Themes: endgame, long, mate, mateIn3, sacrifice.
FEN: 5r1k/R5pp/1p3r2/8/1P2p3/P3P3/3R1nPP/1N4K1 w - - 0 29
Show solution (6 ply)
Try to find the move yourself first — look for the rarest concept firing on this position before peeking. Solution sequence: d2d7 f2h3 g2h3 f6g6 g1h1 f8f1
Concepts that fire on this position
Our SAE pipeline tagged this position with 10 active features. Each links to a page documenting that pattern in detail.
Why this puzzle is hard
The rarest pattern firing here is Detects a black rook on the back rank (rank 8) that is attacked by at least…, which appears in only 5 of our 9,950 puzzles (0.05%). Rare patterns tend to be the bottleneck — players who haven't internalised them will fail this puzzle even when their tactical calculation is otherwise solid.
The puzzle's Lichess ELO of 2059 reflects this: solvers below that rating typically miss the cue entirely.
Similar puzzles
Puzzles sharing the most concept tags with this one — a stronger signal than theme overlap because it reflects the actual patterns Leela recognises.
Train this pattern
Click through to the Climbchess trainer to attempt the position interactively against the same Leela network that tagged it. The trainer adapts difficulty using your live concept-recognition profile — it surfaces puzzles tagged with concepts you've been missing, not random brawls.
If you want the underlying methodology, the how-it-works page walks through the SAE training run, the labelling pipeline, and the puzzle-tagging procedure end-to-end.
Frequently asked
What is the rating of this puzzle?
2059 Lichess ELO. Solvers below that rating typically miss the key cue.
Which side moves first?
White to move; the first move of the solution is d2d7.
What concepts does it train?
10 SAE-derived patterns including A black knight active in enemy territory, often…; Detects white king safely castled on the back rank…; A knight (either colour) that is actively supported by a….
Can I attempt it without an account?
Yes — Climbchess requires no signup or email. Click the trainer link to play the position interactively.