Logic Masters Deutschland e.V.

Hello, I submitted this before with multiple solutions but I am pretty sure this version is finally okay... It's remade from scratch :|

General hints;

Some digits are in common for the two puzzles, named A to G.

The named digits are all different.

Finally, no named digit is less than 2.

Rules (for sum 20 sudoku, scheme on the left);

1. Every group of four cells contained in a 2x2 square has a node in its center, that can be marked or not.

2. For all marked nodes, the corresponding square contains different digits whose sum is exactly 20. (Hint; this rule can also help you remembering the sum of all digits 1 to 9 is...)

3. Whenever a node is not marked, the sum cannot be 20.

Rules (for Shikaku);

Standard puzzle, except you have to guess the clues... The equations underneath the Shikaku hold true, plus a final hint for you;

1. No horizontal or vertical line extends from border to border dividing the puzzle in two parts.