Fillomino: Divide the grid into regions of orthogonally connected cells. Two regions of the same size may not share an edge.
Mathrax: Each clue contains a number and a mathematical operation. For cells diagonally opposite each other across a clue, the number represents the result of applying the operation to the size of those cells' regions.
Hybrid suggested by Qodec.
Play on Penpa
Play on SudokuPad
Example:
Solution code: Row 4, Row 8
on 12. March 2023, 23:18 by Qodec
Incredible!
on 12. March 2023, 21:45 by grkles
Fablous!
on 23. February 2023, 18:08 by OGRussHood
Wow. Just... wow.
on 3. December 2022, 13:18 by SudokuExplorer
Very nicely designed! Lots of clever interactions throughout, thanks!
on 3. December 2022, 11:53 by Piatato
Great puzzle! Such lovely interactions throughout!
on 2. December 2022, 13:59 by Christounet
Very nice puzzle and design ! Loved the logic around the 9x and the 18x clues. Thanks
on 30. November 2022, 11:49 by twobear
Splendid puzzle. Thank you!!
on 28. November 2022, 13:58 by Franjo
Very elegant setting. Not easy, but I enjoyed every single step on the solution path. Thank you very much for sharing this jewel.