(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 | |
|---|---|---|---|
 | 010-er Hochhaus mit PS by julius64 (on 24. December 2010, 00:01) | 44 |  90 % |
| 10-in-9 little killer sudoku by Nylimb (on 22. April 2020, 03:31) | 32 | 97 % |
| Stacked Sandwiches Sudoku by stephane.bura (on 8. July 2020, 08:03) | 52 | 95 % |
| Prime Killer Sudoku by udukos (on 25. July 2020, 17:54) | 47 | 95 % |
| Multi-Way Skyscraper Sudoku by SudokuExplorer (on 18. September 2020, 16:00) | 25 | 97 % |
| Flower by zetamath (on 6. January 2021, 23:12) | 77 | 94 % |
| Blackjack Sudoku-It's all 21 by bigger (on 21. January 2021, 21:21) | 24 | 94 % |
| 33 magnificent dots by PetLov (on 31. March 2021, 10:29) | 35 | 99 % |
| Turtle by Arka Badarka (on 15. July 2021, 04:20) | 25 | 93 % |
| Consecutiveness by Niverio (on 1. August 2021, 11:47) | 52 | 95 % |
| Ultraviolet by grkles (on 13. September 2021, 16:33) | 35 | 98 % |
| The Box by FryTheGuy (on 2. November 2021, 02:22) | 21 | 92 % |
| Noch ein Instructionless by ibag (on 17. February 2022, 23:58) | 19 | 99 % |
| 真笑Puzzles046--Chaos Construction--ZhangYi005 by cdwg2000 (on 13. March 2022, 00:50) | 20 | 97 % |
| Vector Field [Arrow, Killer] by Miky (on 28. April 2022, 19:43) | 21 | 96 % |
| All Around by Joseph nehme (on 22. October 2022, 09:22) | 23 | 90 % |
| Fauteuil by ICHTUES (on 4. December 2022, 06:00) | 21 | 96 % |
| Chain Reaction (Killer Sudoku) by AstralSky (on 5. December 2022, 15:53) | 57 | 92 % |
| Hot Box (Killer, Entropy) by Mad-Tyas (on 19. December 2022, 11:46) | 39 | 91 % |
| Parity Party XXVIII, "Party Mirror" by glum_hippo (on 30. March 2023, 13:57) | 34 | 94 % |
