Logic Masters Deutschland e.V.

This puzzle was originally set in September 2023 for the Cracking the Cryptic Discord's monthly prompt of "Ally McPhee's Ever-Branching Tree."

• Normal sudoku rules apply: Place the digits 1-9 once each in every row, column, and 3x3 box.
• Doublers: Place 9 Doubler cells in the grid so that there is a Doubler in every row, column, and box. Each Doubler must be a different digit. The value of a Doubler is equal to 2 times its digit.
• Region Sum Lines: Values on a blue line must have the same sum for any connected group of cells within a box. Different blue lines may have different sums, and if a single line has multiple groups of connected cells within the same box, each distinct group counts as a separate sum. For example: the line segment in r3c4 is in the same box as the line segment in r123c5, so they each count as a separate sum.

Solve in CTC or f-puzzles