(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 | |
|---|---|---|---|
 | Vampire Whispers by yttrio (on 19. May 2023, 15:27) | 23 |  100 % |
| Saturn's Outermost Ring (Old Version) by loerting (on 15. December 2023, 13:28) | 30 | 94 % |
| River Crossing by IcyFruit (on 22. February 2024, 14:37) | 77 | 98 % |
| MGC-1326 [Masyu Star Battle] by Christounet (on 17. July 2024, 23:54) | 26 | 99 % |
| The Cross by Tom1i (on 15. December 2020, 15:06) | 56 | 99 % |
| Hurricane by SudokuExplorer (on 16. March 2021, 01:00) | 61 | 98 % |
| Chaos Construction: Numbered Rooms / Skyscraper / Sandwich Length by KNT (on 4. May 2022, 07:54) | 51 | 97 % |
| Chaos Fillomino - Border Gaps #2 by Mark Sweep (on 21. December 2022, 10:00) | 31 | 99 % |
| I Refuse to Give Sums! by LittleNightmaresLady (on 26. April 2023, 18:07) | 27 | 98 % |
| Hoverbike by tesseralis (on 10. July 2023, 04:47) | 32 | 98 % |
| Peregrine (13x13 Chaos Deconstruction) by Xendari (on 30. April 2023, 16:27) | 38 | 100 % |
| Arrow Garden by PotatoHead21 (on 22. August 2021, 03:52) | 39 | 98 % |
| Offset Chaos by arbitrary (on 29. January 2025, 00:53) | 41 | 99 % |
| Japanische Höhle mit Irrwisch von den Außerirdischen (2) by ibag (on 20. April 2018, 00:00) | 40 | 100 % |
| Deconstructed Whiski by mathpesto (on 7. July 2022, 20:48) | 51 | 98 % |
| Second Rodeo (collab. with Tallcat) by jwsinclair (on 17. October 2024, 23:06) | 55 | 98 % |
| Dismay (Region Sum Lines Sudoku) by Qodec (on 29. June 2022, 22:50) | 70 | 97 % |
| Roman Whispers (XV German Whispers Sudoku) by Phistomefel (on 31. January 2022, 18:23) | 109 | 98 % |
| Japanische Summen-Koralle Knapp Daneben by Uhu (on 16. January 2017, 21:18) | 47 | 98 % |
| Danke für die tolle Zeit! by ibag (on 10. February 2018, 16:00) | 34 | 99 % |
