(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 | |
|---|---|---|---|
 | Nansuke Sudoku (formerly Word Search Sudoku) by ufdigga (on 13. April 2023, 23:21) | 19 |  97 % |
| Cobweb by antiknight (on 29. June 2023, 19:28) | 20 | 91 % |
| Moriarty Leaves A Clue by HalfBakedLunatic (on 19. August 2023, 23:43) | 51 | 93 % |
| Nightmare on Fillo Street by Jay Dyer (on 7. September 2023, 00:37) | 39 | 97 % |
| XOR #2 by Blashyrkh (on 8. September 2023, 14:06) | 38 | 96 % |
| Zipper Galaxies by gdc (on 4. February 2024, 18:44) | 45 | 98 % |
| Fuzzy Doublers by Oddlyeven (on 24. August 2025, 19:03) | 36 | 94 % |
| The Legend Of Sudoku Hollow: First Encounters by MathGuy_12 (on 31. October 2025, 03:01) | 19 | 95 % |
| Rail Pool by KNT (on 1. January 2026, 19:22) | 21 | 97 % |
| Hurra für Zafer! by Richard (on 30. August 2011, 00:00) | 57 | 97 % |
| Japanese Sums #4: Pinpoint by Myxo (on 5. October 2023, 10:49) | 61 | 98 % |
| Anti-Knight Thermos 2 by Jeet Sampat (on 4. January 2023, 10:47) | 109 | 97 % |
| Angebranntes Kropki by Luigi (on 12. May 2011, 14:55) | 36 | 90 % |
| Donuts [Killer] by Malrog (on 8. October 2024, 00:55) | 47 | 94 % |
| Drift by zetamath (on 11. October 2024, 18:56) | 40 | 98 % |
| Things in common by arbitrary (on 22. April 2024, 11:50) | 68 | 98 % |
| Down for the Count by juggler (on 31. October 2024, 19:06) | 60 | 94 % |
| Archa by zetamath (on 10. January 2022, 06:28) | 100 | 99 % |
| Japanische Koralle 2358 by Uhu (on 30. December 2016, 19:00) | 57 | 98 % |
| Killer Sudoku - Sums or Products by udukos (on 2. November 2020, 20:26) | 42 | 96 % |
