(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 | |
|---|---|---|---|
 | Da Copycat Present by ChinStrap (on 9. May 2026, 01:40) | 30 |  99 % |
| Mystery Box by Jolly Rogers (on 18. October 2023, 11:57) | 66 | 97 % |
| Thermometer Sandwich Sudoku by Jesper (on 31. May 2020, 19:31) | 107 | 90 % |
| 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) | 34 | 97 % |
| REN-BAN by zegres (on 17. October 2023, 05:50) | 52 | 94 % |
| Rank Up 16 - Yin Yang by ralphwaldo1 (on 12. September 2024, 23:49) | 39 | 99 % |
| Dutch Flat Mates : Little Palindrome by goodcity (on 8. April 2026, 07:00) | 46 | 92 % |
| Bäume im Herbst: Mini-Höhle by r45 (on 7. November 2019, 20:00) | 38 | 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) | 51 | 93 % |
| Odd Couples Killer Sudoku by Quarterthru (on 29. August 2020, 12:00) | 46 | 95 % |
| Waves by RandyDan (on 10. January 2026, 12:04) | 43 | 94 % |
| Central Difference Method by JMoat13 (on 25. August 2023, 23:06) | 53 | 93 % |
| Up to N-urikabe by sujoyku (on 29. October 2025, 21:15) | 100 | 98 % |
| Whispers in the Night by ___ (on 13. June 2021, 05:24) | 59 | 95 % |
| Only Thermos by Mesmer (on 20. October 2021, 18:10) | 50 | 95 % |
| Speed Up by ademjaz (on 6. October 2022, 11:04) | 52 | 96 % |
| Dutch Flat Mates (Slingshot) by goodcity (on 15. May 2024, 11:30) | 65 | 90 % |
| Portal Hopping by Gerhard1963 (on 13. September 2024, 22:11) | 60 | 94 % |
