Logic Masters Deutschland e.V.

Normal sudoku rules apply; i.e. the digits 1 to 9 need to be placed, once each, in every row, column, and 3x3 box.

This grid is set on a torus, and only has 100 cells. This means that row 1 and row 11 are in fact the same row. The same is true of column 1 and column 11. Within the grid are 10- 3x3 boxes that must be found. This means that there are 10 cells in the grid that contain no digit. (Blank cells use a zero to solve uniquely)

Digits in a cage must sum to the number in the top left corner of that cage. Digits can not repeat inside a cage.

The larger red circles are clones of one another, so that means that r4c7 is the same digit as r8c2, and r5c7 is the same as r9c2. Also, r5c3 is the same as r9c8, and r5c4 is the same as r9c9.

The medium solid green circles indicate an odd digit.

The medium blue circles are counting circles. A digit inside tells you how many blues circles contain that digit.

The yellow circles and tan lines are 'double arrows', meaning that two circles joined by a line sum to the same sum as the numbers on that line.

Dark brown circles in the corners of cells are quad clues, meaning that a digit listed inside appears at least once in the four cells touching that circle.

Cells separated by a small purple circle must be consecutive.

Cells separated by a small solid black circle must be in a 2:1 ratio.

(also, if anyone knows how to get images displayed in these descriptions, please let me know. I don't think I got this one to work.)

Colored Escape: Riot around and circle back