(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 | |
|---|---|---|---|
 | Hustle and Bustle by taylorsc (on 11. May 2022, 02:23) | 25 |  94 % |
| Loads-N-Kayo by djorr (on 4. July 2022, 14:00) | 26 | 97 % |
| ▜▖Renbanimo Loop▗▛ by ElChiglia (on 30. December 2023, 07:15) | 29 | 95 % |
| LITSomino by mathpesto (on 23. March 2024, 15:48) | 61 | 95 % |
| Loopy Parity X-Sums by yttrio (on 20. July 2024, 02:56) | 27 | 98 % |
| Quantum Irregularities by gdc (on 29. June 2024, 19:13) | 50 | 95 % |
| Miraculous Modular Loop by yttrio (on 22. September 2023, 20:30) | 69 | 94 % |
| Teilchenzoo - Einzelkind by lupo (on 24. February 2013, 07:37) | 36 | 98 % |
| New sudoku variant: Earthquake by grkles (on 14. March 2021, 05:58) | 19 | 99 % |
| Good Friday and Easter Themed - " The Holy Trinity" by MavericksJD (on 2. April 2021, 11:15) | 25 | 94 % |
| Revenge of the Zeros: The sequel by Joseph nehme (on 17. July 2021, 08:56) | 20 | 97 % |
| Rolling Snowballs by Nordy (on 7. December 2021, 22:11) | 21 | 90 % |
| FourCast (Hidden Arrow Sudoku) by Nordy (on 13. December 2021, 05:52) | 43 | 99 % |
| 3D Chaos by mathpesto (on 11. April 2022, 00:20) | 39 | 96 % |
| Three and a Half by Nordy (on 14. April 2022, 08:00) | 18 | 91 % |
| Antithesis (Yin Yang Killer Sudoku) by Agent (on 23. August 2022, 09:00) | 187 | 99 % |
| Wichtel 2022 (8): Kornkreis auf dem Acker by wichtel (on 25. October 2023, 15:15) | 21 | 94 % |
| Squishdoku 245 by Die Hard (on 20. January 2024, 14:11) | 22 | 91 % |
| Pam Li arrow or rail map? by palpot (on 31. January 2024, 17:38) | 29 | 92 % |
| Clockwork Yajilin: Challenger by wisty (on 5. March 2024, 23:10) | 18 | 97 % |
