Logic Masters Deutschland e.V.

Rules:

Normal Sudoku rules apply.

Each cell is located at a certain 'height' (independent of the digit it contains). Cells at height x must only share an edge/corner with cells at height x-1, x or x+1.

A digit at height x hides other digits at height x or below in the line of sight. Clues outside the grid with arrows count the sum of all visible digits in its line of sight. Clues outside the grid without arrows count the number of visible cells in its line of sight.

Try the puzzle on Sudokupad.

Example demonstrating the rules (corner pencil marks denote the height of the cell):