Logic Masters Deutschland e.V.

Koralle (Coral): Shade some empty cells to create a single connected wall (the “Coral”). The shaded cells cannot form a 2×2 square anywhere in the grid, and each unshaded cell block must be connected to an edge of the grid.
Variant: All clued cells are unshaded, and indicate the amount of coral cells found in their row and column combined.
Japanese Sums: Place digits from 1-9 into every unshaded cell (including clued cells, if the clued cell is a letter, the digit to be placed is the corresponding cipher digit) such that no digit repeats in a row or column. Clues outside the grid are Japanese Sums clues, which indicate the sums of the connected unshaded blocks, in correct order. A ? stands for any digit 0-9, but for a double digit clue, the leading ? cannot be a zero. For each row or column, either all or no clues are provided.
Cipher: Clues are ciphered, where each unique letter stands for a different digit 0-9.

Puzzle Links: You can solve this puzzle in either Penpa+ or in CTC. Answer check is included for any correct gray shading and correct number placement, including the cryptic table.