(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 | |
|---|---|---|---|
 | 10-in-9 calcudoku #3 (2021) by Nylimb (on 1. January 2021, 00:00) | 25 |  96 % |
| Kite Setting by thoughtbyte (on 22. August 2021, 19:40) | 28 | 96 % |
| Locked Outside by MavericksJD (on 30. September 2021, 00:00) | 29 | 91 % |
| Close Friends II by mathpesto (on 24. December 2021, 07:06) | 28 | 91 % |
| Rectangles by Sktx (on 19. February 2022, 13:08) | 24 | 95 % |
| Section 8 by XeonRisq (on 16. June 2022, 01:00) | 32 | 95 % |
| Snake Nest Sudoku (chaos construction) by Al Fresco (on 9. December 2022, 20:47) | 26 | 96 % |
| Radar by Jobo (on 10. August 2023, 09:48) | 82 | 93 % |
| EntROPEy by Mad-Tyas (on 2. May 2024, 05:47) | 28 | 95 % |
| Black or White Coral by KNT (on 27. May 2024, 03:47) | 51 | 98 % |
| Kurotto (Aqre) by KNT (on 3. June 2024, 15:44) | 104 | 98 % |
| Bouncing X-sums by Lizzy01 (on 13. March 2025, 12:58) | 27 | 93 % |
| Dark City (skyscraper cave with fog) by SkepticalMario (on 30. November 2024, 11:11) | 75 | 92 % |
| Wichtelkalender 2012 (12) und Schluss by wichtel (on 1. December 2012, 09:00) | 61 | 95 % |
| Dragon Road by Black_Doom (on 14. July 2025, 17:25) | 67 | 98 % |
| Hinges by jovi_al (on 20. December 2021, 02:37) | 132 | 98 % |
| X-Sums Fillomino #3 (4x4x4) by Jesper (on 15. March 2021, 19:53) | 43 | 100 % |
| Pentominous sandwich sudoku by Nylimb (on 28. April 2021, 17:11) | 20 | 97 % |
| Thermal Killer (frei nach Madmahogany) by glum_hippo (on 6. May 2021, 05:30) | 44 | 93 % |
| Introducing Anchor Sudoku! by FryTheGuy (on 8. June 2021, 16:48) | 25 | 94 % |
