(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 | |
|---|---|---|---|
 | Fortune Cookie II by pieguy (on 20. November 2024, 01:23) | 154 |  96 % |
| Thermometer Sandwich Sudoku by Jesper (on 31. May 2020, 19:31) | 104 | 91 % |
| Mystery Box by Jolly Rogers (on 18. October 2023, 11:57) | 66 | 97 % |
| Chaos Construc-to-N by mellowrobinson (on 15. October 2025, 20:10) | 188 | 97 % |
| Floor Plan by the_cogito (on 15. March 2022, 20:39) | 38 | 95 % |
| MAERZ APRIL MAI - Buchstabenrätsel / Letter Puzzle by DocLogic (on 1. March 2024, 01:03) | 33 | 97 % |
| Microclimate by NicoD (on 22. June 2025, 05:30) | 128 | 95 % |
| Vertigo Yajilin #1 by Piatato (on 10. April 2024, 00:37) | 37 | 98 % |
| Archery Contest: XV by I Love Sleeping (on 17. November 2024, 03:21) | 81 | 97 % |
| [New Constraint] Entropy Sudoku by Mad-Tyas (on 3. December 2021, 05:28) | 133 | 93 % |
| Bäume im Herbst: Mini-Höhle by r45 (on 7. November 2019, 20:00) | 38 | 98 % |
| Hakata (Shikaku Chaos Construction) by sfushidahardy (on 29. July 2024, 07:53) | 85 | 98 % |
| Ghost Python 2 (Clone Snake Sudoku) by peterchayward (on 29. July 2020, 19:16) | 46 | 95 % |
| Shuffled by jwsinclair (on 28. November 2023, 21:19) | 50 | 93 % |
| Cross The Streams by Uhu (on 3. August 2024, 21:19) | 41 | 96 % |
| Odd Couples Killer Sudoku by Quarterthru (on 29. August 2020, 12:00) | 46 | 95 % |
| Up to N-urikabe by sujoyku (on 29. October 2025, 21:15) | 94 | 98 % |
| Fillomino-Yajilin-Tapa by CJK (on 4. April 2021, 21:15) | 107 | 100 % |
| Whispers in the Night by ___ (on 13. June 2021, 05:24) | 59 | 95 % |
| Speed Up by ademjaz (on 6. October 2022, 11:04) | 52 | 96 % |
