The following list contains portal puzzles that have been rated as nice or very nice and that are difficult. These puzzles are recommended for experts - and allow some time to solve.
| Description | solved | Rating | |
|---|---|---|---|
![]() | Modular Region Sum Lines Sudoku by Phistomefel (on 7. March 2024, 20:52) | 143 | ![]() 98 % |
![]() | Renban Skyscrapers by Florian Wortmann (on 26. June 2021, 13:41) | 43 | ![]() 92 % |
![]() | The Final Shot: Four Corners 4 (Renban Arrow X) by tallcat (on 7. January 2022, 04:45) | 48 | ![]() 95 % |
![]() | Sacrifission Lambda (Sudokuvania boss) by SkepticalMario (on 13. June 2025, 07:00) | 63 | ![]() 91 % |
![]() | Right Twice a Day by JeffWajes (on 11. August 2025, 05:39) | 50 | ![]() 96 % |
![]() | Mirrors by jovi_al (on 9. June 2021, 06:25) | 96 | ![]() 98 % |
![]() | 58 by Qodec (on 10. October 2020, 16:34) | 49 | ![]() 97 % |
![]() | Anti-Knight Killer Sudoku by SudokuExplorer (on 18. November 2021, 00:00) | 50 | ![]() 94 % |
![]() | Route 5 (Instructionless) by Agent (on 16. January 2024, 09:00) | 47 | ![]() 100 % |
![]() | Ocean Spray by Florian Wortmann (on 6. February 2024, 18:50) | 97 | ![]() 96 % |
![]() | Build Your Own Region Sums by Jay Dyer (on 23. January 2022, 20:27) | 41 | ![]() 99 % |
![]() | The Arkenstone by Blobz (on 11. November 2022, 16:00) | 49 | ![]() 99 % |
![]() | Angels by goodcity (on 8. October 2023, 18:03) | 48 | ![]() 93 % |
![]() | Equally Mad (Dynamic FoW) by gdc (on 13. August 2025, 11:40) | 54 | ![]() 94 % |
![]() | Rätselwochenende: Table for Four - Battleship by uvo (on 26. November 2014, 16:40) | 39 | ![]() 94 % |
![]() | LM-Training: Japanisches Summen-Masyu by rob (on 4. June 2018, 23:22) | 43 | ![]() 93 % |
![]() | Shikaku Fillomino #2 (9x9) by the_cogito (on 15. September 2022, 15:41) | 43 | ![]() 96 % |
![]() | Goldilocks by SudokuExplorer (on 25. May 2021, 01:00) | 44 | ![]() 93 % |
![]() | Pennington by wooferzfg (on 6. October 2022, 05:42) | 41 | ![]() 96 % |
![]() | Foggy Fillomino by Die Hard (on 31. December 2024, 23:24) | 103 | ![]() 95 % |