(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 | |
|---|---|---|---|
 | Mystery Killer Triplets (Little Killer Sudoku) by SudokuExplorer (on 8. August 2020, 03:00) | 20 |  98 % |
| Kropki Indicator Sudoku by udukos (on 4. December 2020, 14:02) | 22 | 97 % |
| Cage Escape (Thermo Killer) by Stavros96 (on 23. February 2021, 10:44) | 45 | 97 % |
| Speaking to the Atmosphere by EliasKar (on 28. April 2021, 13:28) | 20 | 92 % |
| X-sums Chaos Construction by Lizzy01 (on 14. January 2022, 19:18) | 57 | 99 % |
| Thermo x-sums sudoku by Aspartagcus (on 21. January 2022, 08:04) | 21 | 97 % |
| Bittersweet Candies 2 - A Regular 6x6 Sudoku Pack by Playmaker6174 (on 3. July 2022, 20:07) | 20 | 94 % |
| Unplugged by Xenonetix (on 7. August 2022, 02:02) | 55 | 95 % |
| Mauskurven by Myxo (on 21. July 2023, 15:46) | 41 | 100 % |
| Companies (Skyscraper, Product Ltd) by Crusader175 (on 5. December 2023, 14:00) | 19 | 97 % |
| ⬯⬮⬯ Entropic-Sequence-Loop ⬮⬯⬮ (Easter Edition) by ElChiglia (on 30. March 2024, 07:15) | 20 | 94 % |
| The church of not three by filuta (on 29. August 2024, 23:56) | 36 | 97 % |
| Phoenix by ICHTUES (on 25. September 2022, 06:00) | 128 | 96 % |
| Brutalism (Killer Sudoku X) by PulverizingPancake (on 25. June 2021, 21:23) | 61 | 93 % |
| Adventskalender 2023, Türchen 6 - Japanischer Buchstabensalat by Zzzyxas (on 6. December 2023, 07:00) | 52 | 99 % |
| Vierter Pfeilchenstrauß by glum_hippo (on 4. November 2020, 15:53) | 44 | 99 % |
| Quadiagonal by Tyrgannus (on 29. May 2021, 21:19) | 42 | 91 % |
| Baba is Anti-Knight by FryTheGuy (on 16. October 2021, 21:36) | 38 | 98 % |
| Loop Limit by marty_sears (on 24. September 2023, 13:49) | 103 | 97 % |
| Roller Coaster Fillomino #2 (9x9) by Jesper (on 21. April 2021, 09:08) | 51 | 100 % |
