(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 | |
|---|---|---|---|
 | Kill Between The Lines by Djmelee3000 (on 29. September 2020, 02:39) | 43 |  94 % |
| Parity Clockwork by Playmaker6174 (on 20. January 2022, 20:24) | 45 | 96 % |
| Crosswalk by zetamath (on 3. March 2024, 19:32) | 111 | 96 % |
| 10-in-9 killer sudoku #1 by Nylimb (on 25. January 2020, 15:20) | 57 | 95 % |
| Toroidal Chess Sudoku #4 - Queens by Rotstein (on 14. June 2020, 18:44) | 14 | 90 % |
| 12x12 Yajilin / Skyscrapers by stefliew (on 21. July 2020, 18:30) | 27 | 94 % |
| Akari Sudoku by Ringo (on 10. August 2020, 12:27) | 15 | 95 % |
| Surveyor Sudoku by stephane.bura (on 1. October 2020, 20:00) | 14 | 98 % |
| 真笑Puzzles006:Merry Christmas by cdwg2000 (on 19. December 2020, 10:53) | 12 | 93 % |
| Happy New Year 2021 (Sudoku) by Hackiisan (on 31. December 2020, 08:46) | 32 | 92 % |
| Parity Party XVII, "Zum Selberbasteln" by glum_hippo (on 10. March 2021, 06:00) | 24 | 98 % |
| Sudo-Cube by XeonRisq (on 30. August 2021, 00:00) | 42 | 93 % |
| Battle With The Archers - The 14th Target: Archer's Illusion by Playmaker6174 (on 2. September 2021, 16:13) | 37 | 97 % |
| Die Bahn ist immer noch pünktlich, by Dandelo (on 7. September 2021, 23:05) | 11 | 95 % |
| Seven Arrow Carpet Sudoku by jackisaacbryan (on 22. March 2022, 20:34) | 13 | 90 % |
| Wings by Sabrar (on 7. June 2022, 16:17) | 13 | 90 % |
| Pierced by Joseph nehme (on 23. July 2022, 09:01) | 57 | 90 % |
| Wildberry Poptart by Tyrgannus (on 4. August 2022, 11:16) | 115 | 98 % |
| Poison Jar by JeffWajes (on 14. October 2022, 21:30) | 12 | 93 % |
| Juggernaut by Andrewsarchus (on 23. October 2022, 22:20) | 40 | 92 % |
