Sage + Jester · on-device chess
Make the bot
try differently.
Worst Chess Move is a private, offline chess game for iPhone and Android. You play normal chess against Sage, trained to checkmate you, or Jester, trained to checkmate itself. Both run their neural search entirely on device.
- No account
- No ads
- Plays offline
01
Quick start
- Choose your side. Select White or Black on the setup screen.
- Choose your bot and its goal. Pick Sage or Jester, then use As Trained or Inverted to choose what it pursues.
- Start the game. Tap a piece, then tap one of its highlighted legal destinations.
02
Common questions
What does “worst” really mean?
Sage or Jester runs a 400-simulation search with its own bundled neural model. Worst selects the model's lowest valid result; Hard always selects the top. This is the selected model's opinion, not a claim of mathematically perfect chess.
Does the game need internet access?
No. Gameplay and move analysis run entirely on your device. The app has no login, online matchmaking, advertising, analytics, or cloud inference.
Will my game be saved?
Yes. One unfinished game and your setup preferences are kept in the app's private storage on your device. Return to the setup screen to continue that game or start a new one.
How do I change sides, bot, or move mode?
Tap Setup during a game. Your current game remains available to continue until you start a new one, clear the app's storage, or uninstall the app.
How do I promote a pawn?
Move the pawn to its final rank. The app will ask you to choose a queen, rook, bishop, or knight before completing the move.
03
Still stuck?
For help or privacy questions, use the developer contact shown on the app's Apple App Store or Google Play listing. Include your device model, operating-system version, and what happened. Please do not include passwords or other sensitive information.