(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 | |
|---|---|---|---|
 | RedivideR by goodcity (on 17. March 2024, 16:36) | 20 |  93 % |
| Induction (Nonconsecutive German Whispers Sudoku) by Phistomefel (on 14. June 2022, 09:05) | 138 | 96 % |
| Yin Equals Yang by SSG (on 9. September 2022, 07:16) | 57 | 96 % |
| Whispering Knight by Phistomefel (on 22. October 2021, 01:13) | 141 | 94 % |
| Just Wrogn Enough by lerroyy (on 20. May 2022, 18:23) | 68 | 96 % |
| The Corners are Even Double - Double Arrow Even/Odd Sudoku by Mr.Menace (on 29. August 2022, 20:08) | 30 | 93 % |
| Japanese Aquarium by Jay Dyer (on 3. January 2023, 23:06) | 66 | 99 % |
| Wichtels (später) Rätselsommer 2024 (11): Wichtel-Zwietracht by wichtel (on 11. October 2024, 20:23) | 14 | 100 % |
| Chaos Construction: Position Sums (9x9) by Jesper (on 12. October 2021, 20:35) | 79 | 100 % |
| String Quartet by IcyFruit (on 5. November 2023, 01:26) | 74 | 96 % |
| Everything Is Rihgt by DiMono (on 30. September 2022, 03:03) | 93 | 95 % |
| Rigel (Arrow Sudoku) by emmettcito (on 27. April 2021, 17:01) | 41 | 98 % |
| Castle Wall/Cave #2 by MagnusJosefsson (on 28. May 2021, 10:02) | 34 | 98 % |
| Perforate by Xendari (on 14. July 2022, 08:22) | 38 | 98 % |
| Counting Circles in Circles by egubachu (on 16. April 2025, 04:43) | 39 | 94 % |
| Quem Dixere Chaos by mathpesto (on 9. February 2022, 05:06) | 56 | 96 % |
| Squares and Circles by Burning Curtains (on 15. August 2021, 20:17) | 43 | 98 % |
| Despair by XeonRisq (on 3. March 2024, 21:00) | 21 | 97 % |
| Chaos Construction: Liar Japanese Sum (9x9) by Playmaker6174 (on 22. August 2025, 23:00) | 22 | 100 % |
| Perfectly Balanced by IcyFruit (on 13. February 2025, 14:33) | 81 | 97 % |
