(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 | |
|---|---|---|---|
 | It's Gonna Be a Long Knight by cam (on 16. February 2021, 07:04) | 51 |  98 % |
| FourCast (Hidden Arrow Sudoku) by Nordy (on 13. December 2021, 05:52) | 45 | 99 % |
| _234_678_ by twototenth (on 22. February 2022, 08:00) | 48 | 92 % |
| Reuleaux (Arrow Sudoku X) by Ore (on 2. April 2022, 16:00) | 18 | 96 % |
| Smashboy by mathpesto (on 31. July 2022, 20:12) | 72 | 94 % |
| Production Line by starwarigami (on 12. August 2022, 11:41) | 53 | 94 % |
| Whispering Rain by JeremyDover (on 14. August 2022, 23:59) | 26 | 94 % |
| Spindrift by SeveNateNine (on 1. January 2023, 02:49) | 21 | 91 % |
| Switch by fuxia (on 12. March 2023, 01:13) | 60 | 94 % |
| Glider Gun [Akari RGB] by wisty (on 13. October 2023, 14:46) | 28 | 90 % |
| Saturated Chaos by Jeet Sampat (on 3. March 2024, 09:47) | 18 | 97 % |
| Water From A Stone by Biscuit (on 26. August 2024, 18:07) | 45 | 93 % |
| Region Sum and Renban lines by psninn (on 27. September 2024, 20:29) | 71 | 91 % |
| Galactic Orbit by Sniglett (on 10. March 2025, 00:32) | 20 | 98 % |
| Schrödindex by Oddlyeven (on 13. April 2025, 17:40) | 17 | 93 % |
| Looking Left by Md88keys (on 21. July 2025, 15:00) | 24 | 90 % |
| Slipstream (Teleportation Cycle Sums Sudoku) by Feadoor (on 22. July 2025, 10:30) | 16 | 96 % |
| Copycat Banner by Scojo (on 14. September 2025, 02:02) | 17 | 91 % |
| Fantastic 4's and Where to Find Them by Md88keys (on 23. November 2025, 06:47) | 48 | 90 % |
| Entropy Killer by Mad-Tyas (on 8. December 2021, 00:59) | 100 | 97 % |
