(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 | |
|---|---|---|---|
 | Toroidal anti-knight sudoku by Shinya (on 1. May 2020, 11:12) | 22 |  94 % |
| Scrub Python (Palindrome Snake Sudoku) by peterchayward (on 18. July 2020, 11:25) | 47 | 95 % |
| the SAD Sudoku by bigger (on 4. December 2020, 09:57) | 21 | 90 % |
| Quandary Lines by Tyrgannus (on 4. September 2021, 04:09) | 22 | 99 % |
| Combination Lock by Jay Dyer (on 9. December 2021, 00:22) | 18 | 96 % |
| Totally Unfair 2 by Joseph nehme (on 11. December 2021, 08:24) | 22 | 96 % |
| A Year in the Making by Polycarp (on 20. February 2023, 01:19) | 26 | 91 % |
| Madness by jwsinclair (on 12. March 2023, 20:20) | 24 | 97 % |
| Build Your Own Sloopshot by mnasti2 (on 5. September 2023, 17:41) | 23 | 96 % |
| More Drunken Knights by Blobz (on 9. September 2022, 16:00) | 82 | 96 % |
| May XL-Month (5) - Blackout Domino by Richard (on 31. May 2013, 12:00) | 58 | 96 % |
| Bernis Geburtstags-Transporteur by uvo (on 13. June 2013, 21:15) | 26 | 99 % |
| Half The Killer I Used To Be by Djmelee3000 (on 1. September 2020, 00:17) | 31 | 95 % |
| Arrow Dynamics by SSG (on 23. June 2021, 07:58) | 31 | 97 % |
| X---Ternal by riffclown (on 13. January 2022, 00:48) | 26 | 95 % |
| Renbanage by Celery (on 14. November 2022, 00:58) | 29 | 93 % |
| Hybrid Star Battle Series (001) - Tapa-like Loop by BenceJoful (on 8. January 2023, 07:42) | 29 | 92 % |
| Castle Wall / Masyu Liars by Agent (on 24. January 2023, 09:00) | 30 | 99 % |
| Hidden Thermo Sudoku by Prutsbeest (on 28. September 2021, 17:06) | 61 | 97 % |
| Miraculous Modular Loop by yttrio (on 22. September 2023, 20:30) | 62 | 93 % |
