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 | |
|---|---|---|---|
![]() | Yin Yang Arrows by yttrio (on 13. October 2023, 23:06) | 125 | ![]() 98 % |
![]() | Fly Away on my Ziffer by DubiousMobius (on 7. August 2024, 11:54) | 22 | ![]() 97 % |
![]() | Reversing Valve (Dynamic Fog Edition) by ViKingPrime (on 4. June 2025, 15:56) | 52 | ![]() 93 % |
![]() | Floodwaters by Jay Dyer (on 9. July 2022, 00:45) | 73 | ![]() 97 % |
![]() | Sashigane Sudoku by Ambrose (on 14. November 2022, 14:06) | 75 | ![]() 97 % |
![]() | Japanische Summen-Höhle 2358 by Uhu (on 1. August 2017, 22:32) | 48 | ![]() 98 % |
![]() | Coloring Book #9: The Corridor by blackjackfitz (on 23. October 2024, 17:05) | 133 | ![]() 97 % |
![]() | Even Trios Killer Sudoku by Quarterthru (on 14. September 2020, 12:00) | 33 | ![]() 98 % |
![]() | Short THERM 12+1 by Lisztes (on 13. November 2020, 01:00) | 33 | ![]() 90 % |
![]() | BLT by zetamath (on 19. June 2021, 20:30) | 32 | ![]() 98 % |
![]() | Irregional by riffclown (on 2. April 2022, 19:21) | 32 | ![]() 93 % |
![]() | Prime Party by Realshaggy (on 22. September 2022, 01:17) | 29 | ![]() 95 % |
![]() | Variety (6x6 Sudoku Pack) by Florian Wortmann (on 6. June 2024, 12:56) | 35 | ![]() 97 % |
![]() | ABENNR by FullDeck-Missing (on 14. November 2024, 06:20) | 73 | ![]() 95 % |
![]() | Shenanigans by Jay Dyer (on 9. May 2023, 17:11) | 172 | ![]() 98 % |
![]() | Thermography by arbitrary (on 12. December 2023, 16:22) | 76 | ![]() 95 % |
![]() | Counting Reflections by Jolly Rogers (on 18. September 2025, 18:35) | 78 | ![]() 95 % |
![]() | Koralle (5) by Uhu (on 8. November 2020, 11:15) | 38 | ![]() 91 % |
![]() | Juggernaut by Andrewsarchus (on 23. October 2022, 22:20) | 43 | ![]() 92 % |
![]() | SudokOops by Abdul the Killer (on 2. November 2022, 16:52) | 42 | ![]() 91 % |