(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 | |
|---|---|---|---|
 | Double Arrow Sudoku by tesseralis (on 30. June 2023, 03:44) | 24 |  90 % |
| Double Jointed by 99%Sneaky (on 2. September 2023, 19:00) | 20 | 92 % |
| Twin Killer II by Richard (on 25. March 2009, 10:19) | 142 | 95 % |
| Sudoku Variants Series (305) - Encaged Kropki Sudoku by Richard (on 27. January 2021, 00:00) | 64 | 97 % |
| Reflections by EricRathbun (on 1. July 2024, 15:13) | 45 | 96 % |
| Roller Coaster mit Extras by Uhu (on 26. December 2017, 14:22) | 66 | 98 % |
| Chocolate Teapot by Qodec (on 5. May 2021, 16:01) | 73 | 97 % |
| Galaxy Killer Sudoku by Phistomefel (on 11. May 2020, 11:33) | 99 | 96 % |
| Disjoint Killer Arrows by Joseph nehme (on 13. December 2020, 17:11) | 25 | 96 % |
| Killer Sudoku 311 by Quarterthru (on 20. March 2021, 12:00) | 32 | 96 % |
| # (Arrow Sudoku) by Cane_Puzzles (on 4. June 2021, 17:00) | 23 | 96 % |
| Aquarium Escape by zegres (on 6. January 2022, 19:58) | 26 | 92 % |
| Battle With The Archers 26: Reunion (aka Unity II) by Playmaker6174 (on 7. January 2022, 09:17) | 50 | 97 % |
| Multiple Signs by tesseralis (on 9. June 2022, 01:20) | 30 | 96 % |
| Behaving Loop by ElChiglia (on 11. November 2023, 07:35) | 32 | 99 % |
| Tinsel Box by starwarigami (on 28. December 2023, 09:48) | 23 | 95 % |
| Kill Or Quads by MSDOS (on 12. July 2024, 08:26) | 53 | 91 % |
| Daybreak (Antiknight Thermo Sudoku) by Playmaker6174 (on 11. October 2022, 04:47) | 90 | 97 % |
| Poshley Heights by wooferzfg (on 17. May 2023, 06:04) | 30 | 99 % |
| Public Secrecy by shadow-nexus (on 13. January 2024, 00:54) | 34 | 93 % |
