Thermo Square
Rules:
- 6x6 Sudoku:
Every row, column and 2x3 box must contain every number from 1 to 6.
- Killer Cages:
No digit may appear more than once within a cage.
- Thermometers:
Along thermometers, digits must increase from the bulb.
Play it online in SudokuPad.
This puzzle is also on Logic Masters Germany.