I solve Mini Sudoku Level 1 on a 6×6 board starting from 18 clues. 6 irregular regions overlap rows and columns — not classic 3×3 boxes. My hint-driven path uses 18× Naked single across 18 placements.
First pass: scan givens and mark blockers. Most fills come from scanning rows and columns for cells where only one digit fits — classic naked-single territory.
Next 4 fills: R1C1=3, R1C2=2, R2C2=6, R2C6=2. I used Naked single, Naked single, Naked single, Naked single. The naked single at R1C1 opened the chain.
Next 4 fills: R3C2=1, R3C3=2, R3C4=4, R3C5=3. I used Naked single, Naked single, Naked single, Naked single. The naked single at R3C2 opened the chain.
Next 4 fills: R4C2=5, R4C6=1, R4C4=2, R5C2=3. I used Naked single, Naked single, Naked single, Naked single. The naked single at R4C2 opened the chain.
Next 4 fills: R5C3=1, R5C4=5, R5C5=4, R6C1=5. I used Naked single, Naked single, Naked single, Naked single. The naked single at R5C3 opened the chain.
Next 2 fills: R6C4=1, R6C6=3. I used Naked single, Naked single. The naked single at R6C4 opened the chain.
Mid-solve checkpoint: 9 cells remain after the first half of the chain. Row-scan heavy boards often accelerate once two or three regions close — watch for hidden singles in tight blocks.
Late game: final batches collapse quickly when rows and columns near completion. Every row, column, and region contains digits 1–6 with no repeats. Completed path: R1C1=3, R1C2=2, R2C2=6, R2C6=2, R3C2=1, R3C3=2, R3C4=4, R3C5=3, R4C2=5, R4C6=1, R4C4=2, R5C2=3, R5C3=1, R5C4=5, R5C5=4, R6C1=5, R6C4=1, R6C6=3.
Board done — every unit checks out. Most fills come from scanning rows and columns for cells where only one digit fits — classic naked-single territory. Replay without hints using the same scan order.