Little Killer Sudoku

Little Killer Sudoku rules

1. 1
   Rule 1

   The classic row, column, and 3x3 box rules apply as usual.

2. 2
   Rule 2

   Each arrow-marked edge number is the sum of the diagonal cells in that direction.

3. 3
   Rule 3

   There's no extra no-repeat rule along the diagonal itself — only the sum matters.