Logic Masters Deutschland e.V.

This is a 4x4x4 sudoku and each cell is a 1x1x1 cube. Each 4x4 grid shown is one horizontal plane of the cube, each marked with its height order; all are oriented as if looking from above. Normal sudoku rules apply to all possible orthogonal planes of the cube. Digits along an arrow sum to the digit in that arrow's circle. All arrows are contained in their own depicted plane.

Penpa link: https://tinyurl.com/5xxmpmyx

Here's an aid for visualizing: