Normal sudoku rules apply. Place the digits 1-4 once each in every row, column, and 2x2 box.
Thermometer: digits must strictly increase along each thermometer, starting from the bulb.
Cells connected by a V sum to 5. Not all Vs are given.
Digits may not repeat along marked diagonals.
Solve in VariantDoku (iOS) or on SudokuPad.
Solution code: Enter the digits of row 1.
yesterday, 15:01 by superkinkel
I there ever can be a 4x4 more difficult than one star, this is it.
on 8. June 2026, 00:54 by SanFranSam
@electricblue thanks for the hint regarding colouring. Never would have thought of that and given up.
on 7. June 2026, 18:32 by pjot
I loved this. Went from stumped to solved in 1 minute
on 7. June 2026, 18:18 by electricblue
Interesting interaction with all the rules. I didn't expect to be coloring cells on a 2x2 but that was a fun surprise
on 7. June 2026, 14:04 by Freegerator
Baffled why this is getting poorly rated. It’s a fun couple minutes, and it’s hard to have an idea come across in a 4x4 grid