(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 % |
| Sudoku Variants Series (224) - Sum or Product Frame Sudoku by Richard (on 13. March 2018, 00:00) | 98 | 92 % |
| 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) | 51 | 95 % |
| Multi-Way Skyscraper Sudoku by SudokuExplorer (on 18. September 2020, 16:00) | 23 | 97 % |
| Anti-Knight Killer Sudoku #2 by udukos (on 2. March 2021, 10:19) | 60 | 95 % |
| Highs and Lows by RobK (on 26. March 2021, 18:55) | 34 | 95 % |
| 33 magnificent dots by PetLov (on 31. March 2021, 10:29) | 35 | 99 % |
| Diagonal Skyscraper Sudoku by MagnusJosefsson (on 15. April 2021, 16:32) | 37 | 97 % |
| Ultraviolet by grkles (on 13. September 2021, 16:33) | 35 | 98 % |
| The Box by FryTheGuy (on 2. November 2021, 02:22) | 20 | 92 % |
| Tightly Packed by Cane_Puzzles (on 3. February 2022, 12:01) | 85 | 96 % |
| 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 % |
| The Vs by ademjaz (on 12. October 2022, 00:19) | 50 | 92 % |
| All Around by Joseph nehme (on 22. October 2022, 09:22) | 23 | 90 % |
| Mayfair (Anti-King Region Sum Lines) by Xendari (on 8. November 2022, 08:22) | 23 | 97 % |
| Fauteuil by ICHTUES (on 4. December 2022, 06:00) | 21 | 96 % |
| Hot Box (Killer, Entropy) by Mad-Tyas (on 19. December 2022, 11:46) | 38 | 91 % |
| Disoriented (Chaos Construction) by Agent (on 3. January 2023, 09:00) | 43 | 99 % |
