Logic Masters Deutschland e.V.

The Rules:

1. [Sudoku] Normal sudoku rules apply.
2. [Activation Values]: Each cell containing an arrow is an active cell - that is, it is the xth cell into a row or column where x is the digit on the edge of that row or column. Each arrow has an "activation value" equal to x * y where y is the digit in the cell containing the arrow, and x is the digit in the border cell that activated that arrow.
   • If R3c1 is a 9, then R3C9 is an active cell. If R3C9 contains a 4 then R3C9's activation value is 36.
   • If R4C1 is a 1, then R4C1 is an active cell, and it's activation value is 1 * 1 = 1.
   In this puzzle, cells containing arrows cannot contain multiple activation values:
   • If R2C1 is 2 and R2C9 is 8 and R2C2 is 3, then R2C2 has two activation values - 2*3 from the left and 8*3 from the right. This is forbidden.
   • If R9C2 is 8 and R2C9 is 8 and R2C2 is 3, then R2C2 has a consistent activation value of 24 - 8*3 from the bottom and 8*3 from the right. This is ok.
3. [Sandwich] Each row that contains cells with horizontal arrows has a sandwich sum equal to the activation value(s) of the arrowed cells. Likewise with each column and vertical arrows. If a row contains multiple horizontal arrows, or a column multiple vertical arrows, each of those arrows must have the same activation value. A sandwich sum is the sum of the cells between the 1 and 9 in that row/column.

The Puzzle:

Try it on Sven's Sudokupad