(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 | |
|---|---|---|---|
 | Sudoku Variants Series (300) - Killer Skyscrapers Sudoku by Richard (on 22. December 2020, 22:00) | 112 |  97 % |
| Factor Attractor (Ratio Sudoku) by Volatility (on 28. July 2020, 03:10) | 46 | 96 % |
| Broken Ring by Lizzy01 (on 10. January 2021, 20:15) | 28 | 91 % |
| Parity Party XIV, "Avec cages" by glum_hippo (on 4. January 2021, 13:13) | 21 | 94 % |
| Bent arrows by JoWovrin (on 19. June 2021, 13:20) | 44 | 96 % |
| Battle With The Archers 8 - The Climax: Odd Crossroad by Playmaker6174 (on 19. July 2021, 13:00) | 44 | 97 % |
| SunSET Over The Pyramid by zegres (on 20. December 2021, 23:12) | 40 | 96 % |
| A Special Tribute: 1K for Zeta! by Playmaker6174 (on 12. May 2022, 08:42) | 24 | 96 % |
| One by igniteice (on 29. November 2023, 15:48) | 26 | 93 % |
| 7 Boom (Yin Yang). by palpot (on 10. February 2024, 13:55) | 25 | 96 % |
| Cage Growing by Visumation (on 21. October 2024, 15:44) | 67 | 97 % |
| The Good, the Bad and the Circled (fillomino) by SkepticalMario (on 6. February 2025, 14:38) | 24 | 96 % |
| 33 by arctan (on 11. February 2025, 06:21) | 24 | 96 % |
| Cherry Blossom by egubachu (on 25. March 2025, 13:37) | 45 | 99 % |
| Interference by psninn (on 7. April 2025, 14:28) | 49 | 93 % |
| Classic Summation U-bahn by Playmaker6174 (on 6. November 2025, 06:00) | 21 | 97 % |
| Goldilocks by SudokuExplorer (on 25. May 2021, 01:00) | 45 | 93 % |
| Setting the Scene by PjotrV (on 14. October 2021, 15:23) | 47 | 94 % |
| The King With The Arrow by Joseph nehme (on 22. January 2022, 08:12) | 48 | 93 % |
| Equal sum chaos by Testarossa (on 2. June 2022, 16:01) | 45 | 93 % |
