Little Killer Sudoku
In Little-Killer Sudoku the total of each of the diagonals in the grid, other than those 9 cells long, is given. Each number has an arrow next to it which points to the diagonal it gives the sum of, so therefore the top-left cell in this grid must be a 9 thanks to the arrow immediately below and to the left of it. Unlike in regular Killer Sudoku, there is no restriction on repeating digits in any sum.
I’ve also seen Little Killer puzzles which have an additional restriction that no number can repeat on either of the two main diagonals, but I haven’t used that rule here, so numbers can repeat. Apart from the addition of the Little Killer clues, this is a regular Sudoku puzzle.