(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 | |
|---|---|---|---|
 | Confined Sandwich Chaos by PrimeWeasel (on 6. July 2022, 16:55) | 52 |  96 % |
| Fill-a-Renban by SSG (on 23. July 2023, 07:22) | 41 | 95 % |
| In Between the Spaces by XeonRisq (on 12. October 2022, 04:00) | 38 | 95 % |
| BYO Kropki Cages by mathpesto (on 10. December 2022, 02:33) | 69 | 99 % |
| Colour Wheel (Colourful Killers, Rotational Pairs) by The Book Wyrm (on 18. May 2024, 00:55) | 33 | 94 % |
| Chaos Construction by Phistomefel (on 21. April 2020, 00:27) | 135 | 97 % |
| Whispering Knight by Phistomefel (on 22. October 2021, 01:13) | 132 | 94 % |
| Sum Compass Sudoku by stephane.bura (on 31. December 2020, 20:00) | 25 | 100 % |
| Fishnet by TotallyNormalCat (on 22. February 2022, 02:30) | 87 | 97 % |
| Yin Equals Yang by SSG (on 9. September 2022, 07:16) | 55 | 95 % |
| Never (Yajilin/Sudoku) by Wessel Strijkstra (on 6. November 2022, 17:41) | 50 | 95 % |
| Mysterious Boxes by fjam (on 8. January 2023, 16:19) | 25 | 91 % |
| Adventskalender 2023, Türchen 21 - Lügende Passierscheine by Zzzyxas (on 21. December 2023, 07:00) | 25 | 98 % |
| Unique Value Deconstruction by sfushidahardy (on 27. June 2024, 18:13) | 28 | 95 % |
| Tapa / Islands / Narrow Cave Permaculture by KNT (on 3. July 2024, 02:40) | 26 | 100 % |
| Negators by mathpesto (on 20. August 2022, 00:41) | 53 | 96 % |
| Prime-Co Sweepers by XeonRisq (on 11. January 2023, 17:00) | 45 | 100 % |
| Repeat Prescription by Jay Dyer (on 21. July 2024, 00:11) | 47 | 97 % |
| Everything Is Rihgt by DiMono (on 30. September 2022, 03:03) | 91 | 95 % |
| Wichtel 2015 (12 und Schluss): Hommage an eine Künstlerin by wichtel (on 18. July 2016, 21:50) | 34 | 96 % |
