Chess v1

Chess v1

Chess v1 is powered by the Stockfish chess engine, offering a range of skill levels. Its interface is simple to operate, with menu options to customize gameplay, track the state of the game board, and an option to select among a set of "endgame" chess puzzles.

The objective is timeless: outmaneuver the AI opponent and deliver checkmate. The primary challenge comes from Stockfish v11. The user interface has a number of features, including movement of pieces by drag-and-drop operations and a menu with options, such as an undo of prior moves and for starting a new game at a preset skill level. For advanced study, there is an option for loading/saving the game board state in FEN notation format, which is accessible by copy/paste of text.  The current match is also stored in the browser, so as long as this "local storage" is not erased, the match can be resumed at a later time.

Platform

The web browser version supports both desktop and mobile devices. It is run by pressing the `Run game` button at the top of this web page. If on a slower device or for a match that is set at a high skill level, then the underlying chess engine may take up to a few seconds per move which will briefly delay use of the interface of the browser.

Puzzles

The objective is to deliver checkmate in two moves. First, you find the key move that initiates the checkmating sequence. The AI will make its best possible defensive move. You deliver the final checkmating move. It is a classic chess exercise designed to sharpen tactical vision. If a hint is needed, then a best move is available by pressing a button under options under the puzzles section.

Chess v1 includes both a historical and a computationally curated puzzle set, which are accessible under the menu options. The computational data set emerged by a curation process.

The curated set of 329,951 chess positions originated from the "600,000,000 analysed games in the Lichess database". This process included a filter for the puzzle type of interest (theme: mateIn2). Further validation depended on evaluation of each candidate position against the Stockfish v17 chess engine. The engine analyzed positions to confirm the presence of definitive mate-in-two sequences against a computationally perfect defense. The analysis reduced the collection of nearly 330,000 candidates to a set of 1,180 puzzles. This offers a simpler set of puzzles for shorter gaming sessions on a mobile device.

There is a shuffle menu option in the puzzles section to randomize for a selection of 50 of these curated puzzles. They are displayed in the list box before the historical sample. The refresh function in the browser is another way to activate this randomization. Each puzzle record is assigned a unique number for reference and its FEN notation may be retrieved and reloaded under the menu options.