Normal sudoku rules apply. The digits in white circles must appear in at least one of the four cells touching the circle. The digit in the grey cell must be higher than its four orthogonal neighbours. Additionally every edge of the cube sums to the same two-digit number and this number is given in the grid by the 3 two-cell cages (all of which are filled identically), with the tens digit as the top number and the units digit below that.