(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 | |
|---|---|---|---|
 | Stairway to Heaven (collaboration with purpl) by TheRiddler (on 15. October 2021, 17:54) | 25 |  97 % |
| Viewpoint by Xenonetix (on 24. June 2022, 02:22) | 20 | 97 % |
| Bolts by antiknight (on 28. March 2023, 14:49) | 26 | 96 % |
| Confusing the Polarity by Allagem (on 20. May 2023, 08:31) | 21 | 96 % |
| Killer Clones by arbitrary (on 26. January 2024, 16:24) | 22 | 92 % |
| Cavino Seguito (Canal View Nonogram) by PrimeWeasel (on 18. April 2024, 09:10) | 33 | 98 % |
| Projected Cave by KNT (on 10. August 2024, 20:16) | 31 | 99 % |
| Wichtels Rätselsommer 2024 (8): Kakuro-Messfehler by wichtel (on 17. September 2024, 20:23) | 19 | 99 % |
| Exclusion (Thermo Renban Sudoku) by Phistomefel (on 27. March 2023, 18:43) | 124 | 98 % |
| Neue Post vom Außerirdischen by ibag (on 6. September 2015, 00:00) | 61 | 100 % |
| The Sudokutown Murders by Nordy (on 19. February 2022, 04:40) | 61 | 99 % |
| Sudomino by Prof.Dori (on 26. February 2024, 14:27) | 66 | 98 % |
| Japanese Products Sudoku by RockyRoer (on 6. November 2023, 12:00) | 42 | 96 % |
| The Final Move by kolot (on 28. October 2021, 05:01) | 31 | 97 % |
| Five Arrows (Entropy) by Mad-Tyas (on 24. October 2023, 12:48) | 59 | 93 % |
| Adventskalender 2020, Türchen 12 - Landvermessung by Zzzyxas (on 12. December 2020, 07:00) | 55 | 97 % |
| Adamas by Polycarp (on 21. March 2021, 02:30) | 25 | 92 % |
| Cagey Royalty by Jagga (on 11. August 2022, 21:43) | 25 | 99 % |
| Coral Creek by Jay Dyer (on 17. June 2023, 01:07) | 45 | 97 % |
| Think Outside the Box by Jrosas (on 8. April 2024, 07:45) | 51 | 91 % |
