This is a hybrid of Sudoku and Minesweeper. You need both Sudoku rules and the fact that adjacent digits share the mine count on their common edge.
Sudoku: each row, column, and 2×2 box contains each of 1–4 exactly once.
Minesweeper: Each digit equals the total number of mines on that cell's four edges (top, bottom, left, right). Each edge holds 0 or 1 mine.
Pre-painted edges around given clues:
• blue = 0 mines
• red = 1 mine
Unpainted edges are not given — deduce and mark them. (Pen tool under Settings ⚙).
Online play: https://sudokupad.app/ry75tkphdr
Mind the Edge ! 4x4: 000V0F.
Mind the Edge ! #1: 000UYM.
Mind the Edge ! #2: 000UZC.
Mind the Edge ! #3: 000V0U.
Other interesting puzzles:
Magic 30: 000UVI.
7x7 clover sudoku 4: 000UMX.
More of my games: hitodd.com.
Lösungscode: The mine counts on all vertical edges of row 4, read left to right (5 numbers, each 0 or 1).