velvet

Tap a piece, then a dotted square. You play the side shown below the board; the other side responds automatically. Standard chess rules apply, including king safety, castling, en passant and promotion.

The limit counts only your moves. A ◆ and dashed outline mark a capture target, even if it moves. A capture mission ends when that piece is taken; it does not claim that the exchange gains material.

Every move that still forces the mission is accepted. Other legal attempts stay on the board's starting square so you can try again. Undo reverses a whole turn; Reset starts this position again. Hints first suggest an idea, then a piece, then a move.

Keyboard: Tab to the board, use arrow keys to navigate, Enter or Space to select and move; Escape clears selection. All ten levels are available from the menu.

Ten levels each day, selected from 30 bundled positions in a three-day cycle. Each level has three distinct tactical positions; the finite collection repeats. Each day's selection and completed levels are saved on this device when storage is available. Nothing is downloaded during play.

Puzzle positions: Lichess open puzzle database, released under CC0 1.0 Universal. No individual puzzle author is supplied. Level 2 variants advance the source line to its final capture; all other positions apply the database’s setup move. Explanations and interface are original.

Selection and teaching text: Velvet. This page reuses the site’s Afterglow chess engine and interface foundation; its puzzle selection is separate.

Chess rules: chess.js 0.10.3, Jeff Hlywa, BSD 2-Clause. The full notice is below and retained in the inline code. Added internal move hooks for the exhaustive verifier.

Copyright (c) 2020, Jeff Hlywa (jhlywa@gmail.com)
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