(Very) Hard AND nice puzzles
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 | |
|---|---|---|---|
 | Pigeonhole [Renban, Kropki] by Miky (on 26. March 2023, 10:21) | 75 |  90 % |
| Pointer Arrow Parity Loop by yttrio (on 31. May 2025, 01:42) | 116 | 99 % |
| Yin Doubles Yang (Killer + Yin Yang) by damo_89 (on 8. June 2024, 17:24) | 160 | 97 % |
| Wichtel 2017 (9): 26341413052226052223243316041107251607 by wichtel (on 3. October 2018, 05:06) | 26 | 96 % |
| Snake Egg Sum Sudoku by Quarterthru (on 20. July 2020, 20:00) | 17 | 94 % |
| Juggling with the Twins (Partial Killer) by SudokuExplorer (on 2. October 2020, 02:00) | 33 | 91 % |
| Defending Digits (Castle Sudoku) by Mark Sweep (on 14. October 2020, 12:26) | 28 | 95 % |
| 13 by Phurba (on 13. December 2020, 15:59) | 32 | 94 % |
| Octothorpe by Konzert (on 27. February 2021, 20:23) | 20 | 91 % |
| Do Have A Go! by virtual (on 19. May 2021, 06:45) | 13 | 91 % |
| Kaged Knights by kuraban (on 27. June 2021, 02:50) | 35 | 98 % |
| Ghost Digit by jwsinclair (on 15. October 2021, 19:25) | 32 | 95 % |
| Battle With The Archers 22: Double Speculations by Playmaker6174 (on 26. November 2021, 10:06) | 26 | 92 % |
| 3's Company by the_cogito (on 30. November 2021, 20:00) | 12 | 100 % |
| Unique Arrow Sudoku by tsergiiv (on 19. March 2022, 08:07) | 15 | 93 % |
| The Butterfly - (Region Sum/Renban Lines) by Ennead (on 12. September 2022, 20:51) | 15 | 91 % |
| Poison Jar by JeffWajes (on 14. October 2022, 21:30) | 15 | 91 % |
| Modunacci by Goofy (on 16. February 2023, 00:02) | 15 | 91 % |
| Palinsums by SenatorGronk (on 25. April 2023, 18:15) | 13 | 91 % |
| Stopwatch by heliopolix (on 25. August 2023, 18:09) | 36 | 93 % |
