(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 | |
|---|---|---|---|
 | Adventskalender 2023, Türchen 6 - Japanischer Buchstabensalat by Zzzyxas (on 6. December 2023, 07:00) | 60 |  99 % |
| Fortune Cookie by pieguy (on 30. January 2024, 01:53) | 36 | 92 % |
| SudokuCon Quilt by jwsinclair (on 15. April 2025, 21:40) | 83 | 96 % |
| Quadular Arithmetic by MSDOS (on 3. March 2026, 19:41) | 31 | 94 % |
| Calm Construction by oskode (on 16. November 2025, 11:42) | 190 | 97 % |
| Vogelscheuche by Myxo (on 21. July 2024, 13:02) | 101 | 93 % |
| Killer Raute by tuace (on 12. January 2014, 15:30) | 47 | 98 % |
| Japanische Summen-Pentominos 2358 by Uhu (on 14. April 2017, 22:48) | 45 | 96 % |
| Japanische Summen-Höhle Prime/Krypto by Uhu (on 10. August 2017, 19:56) | 42 | 99 % |
| Negator XS by thoughtbyte (on 13. September 2023, 00:55) | 68 | 97 % |
| WSC-Training: Clueless Hidden Classic by JonaS2010 (on 7. October 2019, 18:33) | 60 | 98 % |
| Flying 9s by abed hawila (on 18. December 2020, 19:59) | 18 | 92 % |
| Parity Party XVIII, "Clones" by glum_hippo (on 11. April 2021, 06:00) | 14 | 98 % |
| Alles Gute, Mody! by ibag (on 20. April 2021, 00:00) | 14 | 96 % |
| Albert I, King of the Belgians by Bais (on 13. August 2021, 03:17) | 26 | 94 % |
| Twinkle Twinkle by starwarigami (on 15. May 2022, 21:18) | 14 | 92 % |
| Balanced Sudoku by Nell Gwyn (on 6. August 2022, 04:03) | 14 | 95 % |
| Lookin' Hot by djorr (on 5. December 2022, 14:00) | 17 | 90 % |
| -X Sums by JeremyDover (on 5. October 2022, 23:23) | 16 | 98 % |
| Fusion by Crusader175 (on 7. October 2022, 17:12) | 15 | 94 % |
