How does Thermo Sudoku work? Each sudoku grid contains thermometer shapes (often drawn to create themes) and digits on thermometers must increase as one moves further from the bulb end.

In Killer Sudoku, every puzzle features cages that tell you the sum of the numbers inside. This extra information leads to beautiful logic that you will master as you progress through our handmade puzzles.

Presented by Cracking The Cryptic, YouTube's most popular Sudoku channel, this is the brand new “Classic Sudoku” game that their viewers have been requesting for the last two years!