(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 | |
|---|---|---|---|
 | The Spectrum of Sunlight by egubachu (on 20. December 2024, 15:31) | 46 |  90 % |
| Calembour by Jobo (on 28. May 2025, 09:01) | 36 | 93 % |
| The Yellow Jester (with aqjhs) by ChinStrap (on 16. October 2025, 14:20) | 37 | 97 % |
| 9-Region Thermometers: An Extreme Limitations Puzzle by Md88keys (on 12. July 2025, 21:48) | 112 | 95 % |
| Lace Agate by Niverio (on 4. June 2023, 09:56) | 130 | 95 % |
| Kombisudoku: Chaos - Pünktchen by Richard (on 11. January 2009, 20:28) | 126 | 93 % |
| Tauschpfad (2) by BFaw (on 27. August 2011, 13:20) | 30 | 91 % |
| Thermo-Sudoku: Some Assembly Required by trivial171 (on 6. May 2020, 04:10) | 33 | 99 % |
| Wrapping Paper on Boxing Day by twototenth (on 28. December 2021, 08:00) | 36 | 97 % |
| Dr. Sudoku by Hecspeed (on 9. September 2022, 08:28) | 27 | 98 % |
| Zeta and Kappa by twototenth (on 18. October 2022, 08:00) | 33 | 96 % |
| Diagonalization (Partial CC) by the_cogito (on 31. July 2023, 15:45) | 30 | 98 % |
| HERBST - Buchstabenrätsel / Letter Puzzle by DocLogic (on 28. October 2024, 10:10) | 27 | 97 % |
| Two Times a Killer by EnPee (on 2. January 2025, 00:12) | 27 | 91 % |
| Key West (Nurikabe/Fillomino) by The Book Wyrm (on 7. August 2025, 16:50) | 29 | 100 % |
| A Bigger Squish by marty_sears (on 18. December 2023, 17:35) | 50 | 95 % |
| Yajilin Dutch Whispers by yttrio (on 7. September 2024, 01:37) | 70 | 97 % |
| Message in a bottle by NicoD (on 10. July 2025, 05:30) | 77 | 95 % |
| Chaos Construction: Vision by KNT (on 31. March 2022, 00:50) | 226 | 97 % |
| Skymania: Wolkenkratzer-Hanidoku by Pyrrhon (on 18. September 2009, 12:29) | 62 | 92 % |
