(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 | |
|---|---|---|---|
 | Feudalism (No-touch region sum lines sudoku) by Qodec (on 3. March 2023, 21:26) | 46 |  97 % |
| Mauskurven by Myxo (on 21. July 2023, 15:46) | 46 | 100 % |
| Search Nine Sandwiches by RockyRoer (on 10. August 2023, 05:22) | 21 | 100 % |
| U-Bahn by Piatato (on 14. August 2023, 10:54) | 42 | 99 % |
| 7 Boom (Yin Yang). by palpot (on 10. February 2024, 13:55) | 25 | 96 % |
| Diagonal Regions by Prof.Dori (on 6. October 2024, 14:24) | 21 | 94 % |
| [TSL] damasosos92 would be sad if i don't publish this by Myxo (on 26. October 2024, 14:30) | 20 | 93 % |
| Counter-Clockwise Chaos Construction by sfushidahardy (on 8. November 2024, 04:32) | 59 | 99 % |
| In the Zoo by Qodec (on 21. February 2021, 19:50) | 47 | 90 % |
| The King With The Arrow by Joseph nehme (on 22. January 2022, 08:12) | 44 | 93 % |
| Yin-Yang Thermos by Prof.Dori (on 10. October 2023, 17:23) | 45 | 94 % |
| Modern Art (Easter Special Edition) by Playmaker6174 (on 1. April 2024, 07:00) | 41 | 97 % |
| Loop Count by arbitrary (on 19. September 2024, 21:23) | 45 | 95 % |
| Slitherlink Cave Sudoku by RockyRoer (on 16. August 2023, 14:05) | 63 | 97 % |
| Holographic Principle (Chaos Construction) by sfushidahardy (on 18. July 2024, 04:07) | 151 | 99 % |
| Kropki Indicator Sudoku by udukos (on 4. December 2020, 14:02) | 23 | 97 % |
| Average Arrows (mit Thermometern) by glum_hippo (on 18. January 2021, 22:17) | 20 | 96 % |
| Eleven Arrows by EliasKar (on 3. April 2021, 07:44) | 42 | 97 % |
| Anti-Knight Killer Sudoku by SudokuExplorer (on 18. November 2021, 00:00) | 44 | 94 % |
| Chaos Construction: Arukone by Dandelo (on 17. April 2022, 01:27) | 21 | 95 % |
