(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 | |
|---|---|---|---|
 | Quadruple Knights Out of Order by GBPack (on 23. July 2023, 17:20) | 125 |  94 % |
| Sudoku Variants Series (357) - X-Parity Sudoku by Richard (on 26. January 2022, 00:00) | 72 | 96 % |
| Jetzt gehts rund, Takashi by tuace (on 6. July 2014, 10:30) | 48 | 99 % |
| Quali 2017 - Leftover: U-Bahn by ibag (on 29. January 2017, 20:17) | 52 | 98 % |
| Odd Tapasyu by usp (on 29. October 2014, 00:00) | 46 | 98 % |
| All the Arrows, Big and Small by bboom (on 24. October 2024, 10:06) | 52 | 95 % |
| Arrow or Centipede? by EricRathbun (on 11. September 2022, 18:08) | 46 | 99 % |
| Chaotic Evil by mathpesto (on 29. April 2022, 00:00) | 136 | 98 % |
| Killer Thermo Sudoku by tsc (on 12. February 2021, 21:12) | 32 | 90 % |
| 25 by ICHTUES (on 26. February 2021, 12:26) | 34 | 98 % |
| Hustle and Bustle by taylorsc (on 11. May 2022, 02:23) | 27 | 95 % |
| K⁴NQ⁴ by DarthParadox (on 11. November 2022, 08:24) | 36 | 90 % |
| Square Dancing by EricRathbun (on 1. October 2024, 10:16) | 30 | 91 % |
| Zippular Region Sums by gdc (on 27. March 2024, 19:00) | 28 | 97 % |
| Pentopia by au voleur! (on 14. February 2023, 02:04) | 68 | 92 % |
| A BAD IDEA by PrimeWeasel (on 31. January 2021, 12:10) | 18 | 97 % |
| The Knot by tenaliraman (on 9. April 2021, 00:46) | 43 | 94 % |
| Disjoint 258 Sudoku by Qodec (on 8. October 2021, 18:05) | 62 | 94 % |
| Juosan Division by Jay Dyer (on 16. December 2021, 23:30) | 19 | 97 % |
| Twenty-four and what? by andreasv (on 8. March 2022, 07:37) | 25 | 92 % |
