(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 | |
|---|---|---|---|
 | ← Find-the-Whisper-Loop → by ElChiglia (on 23. March 2024, 07:15) | 34 |  91 % |
| Entropy Killer by Mad-Tyas (on 8. December 2021, 00:59) | 96 | 97 % |
| Arrows, XVs, and Dots by kolot (on 26. August 2021, 09:41) | 44 | 95 % |
| Water From A Stone by Biscuit (on 26. August 2024, 18:07) | 43 | 92 % |
| Kropki XV Puzzle (Oops! No clues!) by RockyRoer (on 5. February 2021, 11:56) | 47 | 95 % |
| OOO OOO by Joseph nehme (on 20. November 2021, 08:07) | 51 | 94 % |
| Production Line by starwarigami (on 12. August 2022, 11:41) | 50 | 94 % |
| Grid Your Lions by cristophermoore (on 16. September 2023, 23:53) | 54 | 91 % |
| Peace Dove by Phurba (on 27. August 2024, 00:07) | 116 | 93 % |
| The Knight and the Knave (Legit/Liar Sudoku) by mathpesto (on 16. August 2022, 23:13) | 75 | 97 % |
| Fortune Cookie II by pieguy (on 20. November 2024, 01:23) | 131 | 97 % |
| My first Sudoku by Selsted (on 12. July 2020, 18:42) | 30 | 91 % |
| Nonconsecutive sandwich killer sudoku by spxtr (on 4. August 2020, 00:53) | 56 | 91 % |
| Cryptic Nurikabe Python by udukos (on 2. January 2021, 16:08) | 16 | 98 % |
| Feeling Left Out by RockyRoer (on 10. February 2021, 11:57) | 18 | 94 % |
| It's Gonna Be a Long Knight by cam (on 16. February 2021, 07:04) | 51 | 98 % |
| Battleships! - Sudoku by JeffWajes (on 28. March 2021, 06:13) | 33 | 97 % |
| Aad-van-ced Irregularity by crispy16 (on 14. May 2022, 05:49) | 18 | 90 % |
| Whispering Rain by JeremyDover (on 14. August 2022, 23:59) | 26 | 94 % |
| Squeez Theorem (Suguru Deconstruction) by KevinTheMH (on 28. June 2023, 21:33) | 27 | 94 % |
