Knight Fever / Showcase
What if a chessboard
had no edges?
Chess: Knight Fever is chess with the volume turned up: a from-scratch engine, a friendly bot and a brutal one, Wi-Fi games across the room, and Endless, chess on a Möbius strip. Completely free, with no ads and no accounts.
Try it: Endless
Glue the a-file to the h-file, with a half-twist.
Endless is ordinary chess on a Möbius strip. A piece that slides off one side comes back on the other, on the mirrored rank: rank 3 becomes rank 6. The top and bottom edges stay edges. Pick a piece, then tap any square to see where it can go.
- Reachable on a flat board too
- Only reachable across the seam ↪
Under the hood, Knight Fever doesn't bend the board. It plays on a flat cylinder 16 columns wide, where columns 8 to 15 repeat the board with ranks mirrored, and projects every move back onto the 8x8 board. This demo uses the same projection.
The engine
Its own engine, written from scratch.
A Swift rules engine and a negamax search with alpha-beta pruning and quiescence search sit behind every bot: a Warm-Up Bot, the Boss at full strength, and a five-rung Bot Ladder in between that slips on purpose so you can climb it. Game Review grades every move of a finished game against the engine's best.
Play the room
Across the room, with no server.
Scan and play
Host a room and a friend joins by scanning its QR code or typing a four-letter code. Games run device to device over your Wi-Fi.
Party Rooms
Up to eight devices around one board: two players, everyone else watching live, with Club Chat and quick reactions.
Nothing to read on the air
Discovery shows a neutral handle. Your name and IDs travel sealed with ChaCha20-Poly1305, and a match runs inside an encrypted session.
Learn and play your way
The engine decides. The coach explains.
The coach runs on your device, trying an MLX model, then Apple Intelligence, then plain templates. The model explains moves but never picks them. The Dojo has 35 guided lessons, puzzles and trainers for endgames, openings and coordinates.
The whole app plays by voice and with VoiceOver, every one of the 64 squares is an accessible element, and every screen went through a WCAG 2.1 AA pass.
Behind the build
From the journal
What if a chessboard had no edges?
Endless mode puts chess on a Möbius strip. How the engine keeps check and checkmate correct across the twist.
Free. No ads. No accounts.
Every mode, every voice and accessibility feature, for everyone.