(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 | |
|---|---|---|---|
 | Nameless Edge(8x8 Self-Hinting Sudoku) by AstralSky (on 15. November 2022, 11:31) | 12 |  93 % |
| Route 75 by mathpesto (on 18. November 2022, 22:16) | 38 | 98 % |
| ModBan Knights by jcgodart (on 27. November 2022, 05:36) | 25 | 91 % |
| Four Five Six by Joseph nehme (on 2. December 2022, 07:58) | 57 | 94 % |
| Sudoku Found in a Viking Grave by Thorsby (on 4. December 2022, 02:19) | 15 | 100 % |
| Xs and Os [Parity, Whispers, Palindromes] by Malrog (on 5. December 2022, 01:42) | 53 | 98 % |
| Killer Battle by 10feet (on 8. December 2022, 05:08) | 19 | 96 % |
| Entroban by jcgodart (on 11. December 2022, 04:56) | 53 | 95 % |
| What's Literally Eating Gilbert Grape by Thorsby (on 11. December 2022, 08:06) | 47 | 97 % |
| Twirl by SudokuExplorer (on 3. January 2023, 14:00) | 49 | 96 % |
| Ambiguous Palindrome by Maxentius (on 21. January 2023, 22:23) | 16 | 94 % |
| The Hot Squeeze by meggen033 (on 31. January 2023, 07:59) | 24 | 91 % |
| Half-Life² by ViKingPrime (on 10. February 2023, 15:32) | 18 | 96 % |
| R you Being Cautious? (RBC 1-6 killer sudoku) by sujoyku (on 10. February 2023, 15:31) | 16 | 96 % |
| Microcircuit by Andrewsarchus (on 20. February 2023, 18:31) | 25 | 95 % |
| Nuclear Safety Inspector by ViKingPrime (on 10. March 2023, 14:00) | 12 | 93 % |
| Sakurairo [Pencilmark Sudoku] by wisty (on 24. February 2023, 03:45) | 32 | 92 % |
| Max Arrows by antiknight (on 3. March 2023, 01:19) | 23 | 94 % |
| Stethoscope by JamesCullum (on 3. March 2023, 02:29) | 13 | 95 % |
| Round the Houses (Killer Loop) by tallcat (on 25. March 2023, 15:37) | 66 | 96 % |
