(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 | |
|---|---|---|---|
 | Japanisches Summen by berni (on 4. September 2015, 21:14) | 28 |  98 % |
| Wichtel 2018 (1): Tapa mit U-Bahn und Hochhaushinweisen by wichtel (on 31. May 2019, 12:08) | 48 | 99 % |
| Bomb Sudoku #2 by Rotstein (on 7. July 2020, 05:00) | 16 | 95 % |
| Parity Party XIII, "Power Hour" by glum_hippo (on 30. October 2020, 14:09) | 23 | 94 % |
| Irregular Compoundoku by athin (on 15. January 2021, 07:00) | 14 | 95 % |
| Sandwiched in Between by udukos (on 16. January 2021, 05:37) | 29 | 99 % |
| Squiggle by Lisztes (on 11. April 2021, 01:00) | 30 | 96 % |
| The Cross by Lisztes (on 21. March 2021, 01:00) | 11 | 95 % |
| Thermo Sandwich (<>) Sudoku by Cane_Puzzles (on 23. April 2021, 18:00) | 25 | 98 % |
| 7 (Arrow X Sudoku) by ICHTUES (on 25. April 2021, 06:00) | 39 | 93 % |
| Decidoku by Innocuous (on 18. August 2021, 01:31) | 18 | 95 % |
| Dance Partners / Die Tanzpartner by Auul (on 13. September 2021, 07:44) | 12 | 93 % |
| Framed Bats by Emphyrio (on 2. October 2021, 18:53) | 23 | 95 % |
| Nonconsecutive Palindrome Sudoku #1 by GBPack (on 24. November 2021, 22:15) | 19 | 93 % |
| The X Days of 12-Mas by Mojo872 (on 1. December 2021, 16:49) | 19 | 90 % |
| Kropki XV Sudoku - Progressive Power-Up by DiMono (on 6. January 2022, 18:46) | 28 | 93 % |
| Odd Turtle Sudoku by Thorsby (on 10. June 2022, 05:02) | 18 | 98 % |
| Watched (Run-on Renbans) by riffclown (on 12. September 2022, 00:18) | 40 | 98 % |
| Cubic Doublers by Blobz (on 7. November 2022, 16:00) | 34 | 91 % |
| Kropki a-lien by chameleon (on 15. October 2022, 02:59) | 17 | 93 % |
