Logic Masters Deutschland e.V.

Normal 9x9 Sudoku: Place the digits 1-9 exactly once in every row, column, and 3x3 box.

Thermometers: There are filled circles in the grid with connected thick lines called thermometers. The circle represents the bulb of the thermometer. Digits must strictly increase along the thermometer starting from the bulb end.

Quadruples: There are circles in the grid which occupy the corners between some cells called quadruples. Digits in the circles must all appear at least once in the cells touching them.