(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 | |
|---|---|---|---|
 | Odd Blockade Runners by JeffWajes (on 17. April 2023, 19:44) | 110 |  96 % |
| Full House by juggler (on 20. June 2024, 01:17) | 106 | 97 % |
| Undeca Error (Killer, Anti-Knight) by Chilly (on 5. September 2022, 19:28) | 96 | 96 % |
| Binary star by NicoD (on 9. April 2025, 05:47) | 95 | 97 % |
| Box killer sudoku by udukos (on 20. August 2020, 11:06) | 71 | 97 % |
| Frak Redux (Ten Lines) by tallcat (on 25. October 2023, 09:00) | 62 | 95 % |
| Wichtel 2019 (10): Die Wohnquartiere der Wichtel by wichtel (on 2. November 2020, 19:20) | 54 | 100 % |
| Sompeo (Encaged Whispers) by ICHTUES (on 31. July 2022, 06:00) | 67 | 94 % |
| U-Bahn (2) by KNT (on 15. April 2023, 06:02) | 59 | 99 % |
| Skystaplers by ChinStrap (on 1. July 2025, 15:59) | 60 | 98 % |
| Zwei Rundwege aufeinander by Micha (on 31. December 2010, 16:04) | 46 | 98 % |
| Memphis by ICHTUES (on 20. February 2022, 06:00) | 52 | 95 % |
| Cave Sudoku by Phistomefel (on 10. July 2020, 12:39) | 99 | 96 % |
| Tetrakiller by Jay Dyer (on 31. May 2022, 15:17) | 91 | 97 % |
| Noch ein runder Rundweg 2 by Calavera (on 11. August 2009, 18:09) | 41 | 98 % |
| Differenz X Kakuro IV (kryptisch) by tuace (on 31. August 2014, 21:30) | 42 | 97 % |
| Dutch Fillomino Mates by mathpesto (on 10. April 2025, 22:32) | 49 | 99 % |
| Dutch-pelgänger by ChinStrap (on 6. December 2025, 16:19) | 80 | 96 % |
| Viper in the fog by Jolly Rogers (on 15. June 2024, 10:00) | 128 | 95 % |
| Roller Coaster mit Extras 4 by Uhu (on 22. February 2018, 09:27) | 67 | 100 % |
