(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 | |
|---|---|---|---|
 | Roller Coaster U-Bahn by Zzzyxas (on 22. August 2019, 18:25) | 58 |  99 % |
| Three Arrows by Onion Suit (on 5. May 2021, 02:31) | 24 | 94 % |
| Wave Sudoku by Vebby (on 26. May 2021, 19:06) | 18 | 95 % |
| Diamonds by abed hawila (on 6. June 2021, 17:16) | 20 | 96 % |
| Norinori Castle Wall by SudokuExplorer (on 11. March 2022, 17:30) | 20 | 94 % |
| Rounded Repulsion by Qril (on 9. June 2022, 02:04) | 21 | 96 % |
| Mineshweepa by mnasti2 (on 10. August 2022, 20:45) | 24 | 94 % |
| Abstract Nonsense by Oddlyeven (on 13. August 2022, 23:34) | 74 | 97 % |
| Second Region X-Sums Chaos by Elliptical (on 20. November 2022, 21:22) | 44 | 98 % |
| Double Arrow Sudoku by tesseralis (on 30. June 2023, 03:44) | 25 | 91 % |
| Mixed Doubles by marty_sears (on 28. August 2023, 18:38) | 71 | 96 % |
| Double Jointed by 99%Sneaky (on 2. September 2023, 19:00) | 23 | 93 % |
| Dissident Factions by meggen033 (on 28. January 2024, 06:14) | 41 | 91 % |
| el quinto sol by aqjhs (on 27. November 2024, 05:00) | 23 | 96 % |
| Then I Took A Pill Arrow To The Knee by ChinStrap (on 22. February 2026, 20:30) | 56 | 97 % |
| Pentominous Sum Lines by Xendari (on 19. October 2023, 23:22) | 63 | 97 % |
| Heat Exchange by EdTheAlchemist (on 9. November 2025, 11:08) | 80 | 96 % |
| XX Sandwich by Tomatenalat (on 15. September 2024, 11:46) | 109 | 96 % |
| Cavalry Archer (Anti-Knight Arrow Sudoku) by Phistomefel (on 2. June 2021, 21:09) | 200 | 97 % |
| Little Parity Party Sudoku by MagnusJosefsson (on 21. March 2021, 00:32) | 23 | 96 % |
