(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 | |
|---|---|---|---|
 | Slices by Joseph nehme (on 31. July 2021, 12:43) | 45 |  96 % |
| Hidden Thermo Sudoku by Prutsbeest (on 28. September 2021, 17:06) | 62 | 97 % |
| Anti-Knight, Arrows, Killer Cages, and Kropki Dots by Jeet Sampat (on 31. October 2021, 01:11) | 37 | 92 % |
| Reuleaux (Arrow Sudoku X) by Ore (on 2. April 2022, 16:00) | 16 | 96 % |
| Regular Tetragons by Oddlyeven (on 18. July 2022, 02:04) | 19 | 92 % |
| Floody Hekc by Malrog (on 30. July 2022, 01:38) | 14 | 98 % |
| The Oculus by Ennead (on 1. October 2022, 18:06) | 15 | 94 % |
| Happy Halloween! (Shifted X-sums 3) by Lizzy01 (on 27. October 2022, 19:48) | 15 | 94 % |
| X-Lines Sudoku by dennischen (on 19. February 2023, 20:21) | 15 | 92 % |
| Nothing's Funny (XV, Killer, Renban) by Chefofdeath (on 15. June 2023, 20:47) | 37 | 94 % |
| Find and Take Out The Killers by RockyRoer (on 19. September 2023, 03:17) | 47 | 97 % |
| My Zipper is Broken by marty_sears (on 26. February 2024, 14:53) | 101 | 98 % |
| Take U-Turns by Black_Doom (on 20. March 2024, 04:35) | 47 | 96 % |
| Twister by Prof.Dori (on 22. May 2024, 14:06) | 51 | 91 % |
| Ratsnake (Loop/German Whispers/Parity/X Sums) by damo_89 (on 19. August 2024, 13:06) | 16 | 92 % |
| Copycat Mates by Scojo (on 28. October 2024, 02:33) | 15 | 90 % |
| Corner Pockets by thoughtbyte (on 6. September 2022, 21:07) | 74 | 95 % |
| DSM Qualitraining 2021: Parity Party Sudoku by Realshaggy (on 16. January 2021, 06:00) | 52 | 96 % |
| Median Killer Sudoku by RockyRoer (on 11. June 2021, 14:00) | 51 | 98 % |
| Japanische Summen - Krypto by ibag (on 22. July 2012, 09:20) | 81 | 99 % |
