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Symbiosis Chess
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About the game
In Symbiosis Chess you and the strongest chess engine in the world are on the same side. You play as White, and you make your moves as usual, but the engine plays every other move of yours for you. So you open with a move of your choosing, then Stockfish makes your second move, then you make the third, and so on. Your opponent answers each of them.
That changes the game in a quiet way. You can not count on a plan lasting more than one move, because the next move will be the engine's, and its idea may be completely different from yours. You have to set up positions that survive a strong, unpredictable partner, and take advantage of the moves that are suddenly very good. The opponents are mascots of well-known free-software projects, each shown with a rating.
Playing it here
Click Play, press Start, then Begin and pick an opponent. The engine runs inside the page, so the first move of the engine can take a moment; no game data is sent anywhere. Settings are kept in your browser only.
Controls
| Input | Action |
|---|---|
| Click or tap a piece, then a square | move the piece |
| Resign button | give up the game |
A few things worth knowing
You only choose half of the moves. Keep your own moves flexible, since the engine will play the next one.
Do not undo the engine's work. If it just made a strong move, build on it instead of pulling the position apart.
The ratings are a guide. The Elo shown for each opponent tells you how strong that mascot plays.
Questions
Is Stockfish really playing? Yes. The game runs the Stockfish engine inside your browser, in a single thread, so it is a bit weaker than on a desktop but still much stronger than most players.
Does it work on a phone? Yes, tap a piece and then its destination.
Credits and licence
Symbiosis Chess was made by dtsudo as an entry for a free-software game jam and is published under the GPL-3.0. It uses Stockfish through Stockfish.js (GPL-3.0), whose logo is used here only as the picture of the engine, and chess.js (BSD-2-Clause) for the rules. The chess pieces are by Cburnett (BSD), the images of Kenney and the sound effects of Kenney are CC0, and the fonts (Roboto and a font from metaflop) are under the SIL Open Font License. The opponents are free-software mascots: Tux (the SuperTux team, GPL-3.0), Konqi and Katie by Tyson Tan (CC BY-SA), Kiki by Tyson Tan (CC BY-SA), and Wilber, the GIMP mascot, by Aryeom Han (CC BY-SA). The music "Sci-fi Theme 1" is by maou (CC BY 4.0). The licence texts are in the licence file linked from this page. The Stockfish.js engine (GPL-3.0) is served as published by the game's author; its source (stockfishSourceCode.zip) is hosted here. The neural networks embedded in its .wasm are not part of that source: the build scripts in it download them from tests.stockfishchess.org, where they are published under the same GPL-3.0 terms. We changed three things: a policy that stops the page from loading anything from other sites, the link to the author's GitHub page (it does nothing here), and the browser-save keys, which get a prefix so they do not clash with other games.