(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 | |
|---|---|---|---|
 | Rorschach by zetamath (on 12. November 2024, 16:42) | 77 |  94 % |
| Down The Drain Arrow Sudoku by bram (on 18. September 2020, 21:40) | 42 | 96 % |
| Interval Sums Sudoku by Qodec (on 28. November 2021, 02:08) | 38 | 94 % |
| Jetzt gehts rund, Takashi by tuace (on 6. July 2014, 10:30) | 47 | 99 % |
| Schrödinger 203: Quantum Tunnelling by ViKingPrime (on 30. September 2023, 00:30) | 53 | 97 % |
| Pac-Man Sudoku by mathpesto (on 10. June 2023, 04:50) | 127 | 94 % |
| Wichtel 2011 (11): Ein 3D Japasumino by wichtel (on 14. March 2012, 09:00) | 61 | 92 % |
| Sudoku Variants Series (357) - X-Parity Sudoku by Richard (on 26. January 2022, 00:00) | 62 | 95 % |
| Smashboy by mathpesto (on 31. July 2022, 20:12) | 65 | 95 % |
| Starmie (Masyu-Star Battle Hybrid) by MaizeGator (on 18. February 2025, 03:12) | 61 | 95 % |
| Odd Tapasyu by usp (on 29. October 2014, 00:00) | 45 | 98 % |
| Parity Runs #3: Skyscraper by Madmahogany (on 10. June 2020, 20:17) | 44 | 94 % |
| Floor Plan by the_cogito (on 15. March 2022, 20:39) | 36 | 95 % |
| Daedalus by jovi_al (on 18. October 2022, 20:36) | 47 | 90 % |
| A tilt at full rank by ralphwaldo1 (on 8. February 2025, 19:16) | 87 | 98 % |
| Prime whispers sudoku (aka "Prime line sudoku") by ibn Muhyiddin (on 4. July 2020, 16:32) | 58 | 96 % |
| Radical Region Sum Loop by yttrio (on 17. November 2023, 21:25) | 60 | 95 % |
| Thermo Miracle Sudoku by SudokuExplorer (on 7. July 2020, 18:05) | 97 | 90 % |
| Two-Zip by AFrayedKnot (on 8. October 2024, 08:34) | 52 | 95 % |
| Chained Killer Sudoku no. 2 by Shinya (on 21. February 2020, 22:48) | 33 | 95 % |
