(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 | |
|---|---|---|---|
 | Mönch (Killer sudoku) by Qodec (on 13. December 2023, 21:51) | 75 |  95 % |
| Divide and Conquer by ebiggie (on 30. November 2025, 00:10) | 82 | 97 % |
| Destin Sunset (YIN-Yang Fillomino) by MaizeGator (on 1. August 2024, 15:39) | 49 | 98 % |
| e m p t y = c h a o s by aqjhs (on 28. December 2024, 06:15) | 76 | 98 % |
| Whispering Arrows by antiknight (on 8. April 2022, 22:57) | 27 | 98 % |
| Black Eyes by Qodec (on 10. April 2022, 14:31) | 31 | 95 % |
| Astronavigation by fjam (on 15. July 2023, 13:12) | 25 | 100 % |
| Wasteland [Landvermessung/Chaos Deconstruction] by zzw (on 16. April 2024, 13:26) | 30 | 95 % |
| Cygnus (Kurodoko + Yajilin Amalgam) by sfushidahardy (on 29. October 2024, 04:23) | 31 | 99 % |
| Wichtel 2018 (7): Das historische Rätselhausen by wichtel (on 13. December 2019, 21:08) | 31 | 99 % |
| Roller Coaster Cipher by ONeill (on 16. June 2024, 16:26) | 34 | 99 % |
| Anti-Springer Killer, "Das Stundenglas" by glum_hippo (on 4. November 2020, 01:26) | 51 | 94 % |
| Twilight Nurikabe by KNT (on 3. January 2023, 02:12) | 43 | 99 % |
| Jumelage [RSL Renban Twin Sudokus] by Christounet (on 22. October 2024, 13:09) | 40 | 96 % |
| Japanische ABCtje-Summen by ibag (on 22. September 2012, 00:08) | 57 | 99 % |
| XV*Magic 7 by NurglesGift (on 10. January 2025, 23:18) | 90 | 97 % |
| Castle Wall Delta #1 (10x10) by Jesper (on 22. May 2021, 17:38) | 77 | 97 % |
| Ein JaTaHoKu by Statistica (on 27. October 2011, 15:00) | 68 | 97 % |
| Dual Slitherlink by Phistomefel (on 8. May 2020, 11:09) | 64 | 97 % |
| The Devil's Arrows by Lisztes (on 22. February 2021, 01:00) | 24 | 96 % |
