(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 | |
|---|---|---|---|
 | Jigsaw Sudoku II by Richard (on 17. March 2009, 14:44) | 133 |  90 % |
| Wichtel 2014 (14 und Schluss): Durch den Zauberwald by wichtel (on 17. April 2015, 01:42) | 33 | 98 % |
| Schwarz oder Weiß Koralle III by tuace (on 4. October 2015, 17:09) | 48 | 96 % |
| Geburtstagsgruß by ibag (on 20. April 2019, 00:00) | 25 | 90 % |
| Parity Party V — "Vortex Temporum" by glum_hippo (on 19. April 2020, 06:21) | 35 | 92 % |
| Killer Battlefield Sudoku : Enigma by Carrick22 (on 29. May 2020, 12:14) | 37 | 96 % |
| Wärmetod by glum_hippo (on 3. September 2020, 17:55) | 17 | 93 % |
| Crossguard Lightsaber Sudoku by Stavros96 (on 29. October 2020, 13:01) | 27 | 94 % |
| Fünfter Pfeilchenstrauß, "Quer Beet" by glum_hippo (on 8. December 2020, 16:37) | 28 | 95 % |
| Shy Magic Square Sudoku by ICHTUES (on 21. February 2021, 06:00) | 22 | 93 % |
| Ambiguity 2 by zetamath (on 13. April 2021, 02:44) | 47 | 94 % |
| Wichtel 2020 (6): Rundweg "Fünf Jahreszeiten" by wichtel (on 27. May 2021, 20:02) | 40 | 99 % |
| All Crossed Up by Polycarp (on 13. May 2021, 04:45) | 27 | 95 % |
| The Fairest in the Land (Inequality Series #6) by twototenth (on 19. October 2021, 08:00) | 19 | 91 % |
| Four Lockout Lines by Lizzy01 (on 30. October 2021, 17:19) | 35 | 98 % |
| Marupeke Sudoku by Crusader175 (on 7. November 2021, 08:08) | 27 | 92 % |
| Hidden Sums by jwsinclair (on 27. November 2021, 20:19) | 40 | 97 % |
| The 28th Party (CTC Secret Santa 2021) by Niverio (on 29. December 2021, 00:11) | 79 | 97 % |
| Integral Magic Squares by mathpesto (on 16. April 2022, 18:32) | 19 | 93 % |
| Constellation by tenaliraman (on 15. July 2022, 09:03) | 46 | 96 % |
