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Games about AI: ⌨ Prompt · 🧠 Overfit · 🧪 Mimic · 👁 Overseer · 📉 Minima · 🏭 Singularity Inc. · 🏎 Ghostline · 💥 Block Nova
Most days need no given numbers at all — the dots alone pin the grid. Sister puzzles: Gridlings.
Fill the grid so every row and column holds each number once. A white dot between two cells means they differ by exactly 1, a black dot means one is double the other, and no dot means neither relation holds — the absence is a clue too.
Yes — a new daily board goes live at 00:00 UTC, the same board for every player worldwide, with streak tracking. Unlimited free play in three difficulties and a full archive of past dailies are also free, with no account and no ads.
Yes. Every published board is machine-verified before release: a solver proves exactly one solution exists and is reachable by logical deduction, so there is always a provable next step.