(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 | |
|---|---|---|---|
 | Chaos Construction: Region Counting by KNT (on 28. April 2022, 17:59) | 49 |  96 % |
| Saturnalia by mathpesto (on 13. January 2024, 05:19) | 69 | 94 % |
| Vertigo Yajilin #2 by Piatato (on 7. May 2024, 17:47) | 14 | 100 % |
| Doubler Trickery by Mad-Tyas (on 12. October 2024, 12:33) | 15 | 91 % |
| Colossal Slitherlink Sudoku by Agent (on 5. September 2023, 09:00) | 45 | 99 % |
| Spotlight (Anti-King Arrow Sudoku) by EliasKar (on 5. May 2021, 18:18) | 27 | 99 % |
| Blackadder by udukos (on 30. May 2022, 12:14) | 52 | 97 % |
| Country Road Fillomino #1 (10x10) by Jesper (on 10. October 2022, 15:41) | 58 | 98 % |
| Space Mountain by IcyFruit (on 1. December 2023, 22:12) | 24 | 97 % |
| Genome by Tyrgannus (on 7. July 2021, 21:33) | 38 | 97 % |
| Parhelion by Shinya (on 2. September 2021, 00:09) | 66 | 99 % |
| Chaotic Skyscraper Sums by Florian Wortmann (on 6. August 2022, 16:04) | 80 | 99 % |
| Exploded Compass Sudoku by stephane.bura (on 7. January 2021, 20:00) | 32 | 100 % |
| Daredevil (clone + thermo sudoku) by Aspartagcus (on 4. March 2021, 22:21) | 45 | 94 % |
| Binary Quantum Void by DadJokes (on 13. October 2022, 19:14) | 25 | 94 % |
| The Digits Are Paid Actors by Lizzy01 (on 5. November 2022, 21:40) | 21 | 99 % |
| Oklahoma City by ICHTUES (on 27. November 2022, 06:00) | 65 | 96 % |
| Abstract Art (Equalines, Entropy) by Mad-Tyas (on 27. February 2023, 09:16) | 35 | 97 % |
| A Rose by PotatoHead21 (on 2. August 2023, 08:24) | 31 | 94 % |
| Productivity Killer (BYOK+) by SeveNateNine (on 18. October 2023, 02:45) | 19 | 99 % |
