(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 | |
|---|---|---|---|
 | War with Pythagoras by JeffWajes (on 20. July 2025, 11:39) | 88 |  96 % |
| Guillotine by Qodec (on 4. September 2022, 12:20) | 55 | 95 % |
| This + This = That by EricRathbun (on 1. November 2023, 15:55) | 49 | 97 % |
| Edelweiß by loerting (on 27. December 2023, 23:20) | 56 | 95 % |
| Mousetrap? (A Rat Run Homage) by tallcat (on 16. January 2025, 06:00) | 229 | 98 % |
| 4th of July Encrypted Thermo-Sandwich by Alexander Rappa (on 3. July 2020, 16:15) | 31 | 92 % |
| Killer Wasp by Quarterthru (on 31. May 2021, 12:00) | 31 | 97 % |
| Arrows and a Big X by GBPack (on 17. June 2021, 17:11) | 29 | 97 % |
| Stacked - Arrow Sudoku by Mr.Menace (on 6. July 2021, 20:51) | 49 | 97 % |
| Multiple Signs by tesseralis (on 9. June 2022, 01:20) | 32 | 97 % |
| Room Service by Xenonetix (on 9. October 2022, 02:02) | 27 | 93 % |
| Distinctiveness by Ridhwan (on 12. February 2024, 00:05) | 26 | 92 % |
| Echoing Cages by graggle (on 26. April 2025, 11:00) | 61 | 96 % |
| Gingham Games by SingingFish (on 7. March 2026, 22:21) | 31 | 92 % |
| Japanische Hochhaus-Summen (Mini-Krypto) by ibag (on 21. September 2012, 22:04) | 56 | 98 % |
| Wichtel 2019 (9): Hybrid by wichtel (on 4. October 2020, 19:02) | 36 | 99 % |
| Areal Sudoku by ICHTUES (on 4. February 2021, 12:26) | 76 | 95 % |
| Bubbles by alexc (on 20. March 2024, 03:30) | 38 | 93 % |
| Seilkunde by Blashyrkh (on 16. May 2024, 17:40) | 39 | 96 % |
| Cover Up (Tapa Sudoku) by tallcat (on 3. April 2025, 06:00) | 78 | 95 % |
