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LIGHT CYCLES

Light Cycles

A grid arena with lethal trails. Every cycle lays a wall it can never cross — including its own — so the room you are in is the room you have made. A 180° turn is never offered, two cycles that reach the same cell on the same tick both die, and the walls close in on a schedule so every match is guaranteed to end. The solo mode is the unusual part: the solver PROVES the maximum number of cells one cycle can occupy, and scores you against it.

👥 Local Hot-Seat Two to four players on one keyboard: arrows, WASD, IJKL or the numpad. Hold Shift to boost.
🤖 vs Computer Three deterministic levels. Level 3 searches simultaneous move pairs, which costs 20–195 ms a tick — so it runs in a Web Worker, and the arena never stutters.
🌍 Online Arena A room code, two to four cycles, and a server that owns the CLOCK: your keypress becomes an intent that lands on the next tick, so two clients can never disagree about who hit whom.
🧮 Solo Survival One cycle, one empty arena. The solver computes the exact maximum number of cells you can occupy and proves it: a counting bound from above, a construction from below, and the engine replays the witness before the number is published. Boost, decay and shrinking walls are forced OFF here, because those break the ceiling the proof rests on.
Best possible: —
Local
Tick 0
Arena 40 × 24

Arrows / WASD / IJKL / numpad steer. Shift boosts. Space pauses. A turn lands on the NEXT tick, and a 180° turn is never accepted.

Settings

Arena

The engine accepts any axis from 3 to 80; the UI offers the nine sizes the E2E suite sweeps. Non-square arenas are the interesting ones — the default 40 × 24 is a widescreen — and the spawn set is always closed under 180° rotation, so no seat starts structurally better off.

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Rules

The pattern is grown in the top-left quadrant and mirrored, so a seed reproduces a board exactly and both players face the same arena.

Sudden death is the termination guarantee, not a decoration: the free area strictly decreases at every inset, so a match is bounded by arithmetic rather than by hope. Turning all three off makes a position the survival solver can certify.

The proof

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