(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 | |
|---|---|---|---|
 | 23 Killer by Florian Wortmann (on 18. January 2023, 18:50) | 82 |  95 % |
| Interval Sums Sudoku by Qodec (on 28. November 2021, 02:08) | 44 | 94 % |
| Pinch Yourself (Killer Sudoku) by purpl (on 1. February 2022, 22:31) | 67 | 96 % |
| Entropy Fish by Ridhwan (on 3. November 2023, 16:36) | 72 | 96 % |
| SPION-AGENT-KUNDSCHAFTER Buchstabenrätsel by DocLogic (on 16. March 2021, 14:14) | 39 | 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) | 26 | 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) | 23 | 90 % |
| Equal Color Sums by rmahus (on 6. January 2022, 08:00) | 22 | 93 % |
| Balance = Entropy by JeremyDover (on 12. February 2022, 23:59) | 116 | 99 % |
| Three and a Half by Nordy (on 14. April 2022, 08:00) | 18 | 91 % |
| Arrow Bites by PotatoHead21 (on 30. October 2022, 21:57) | 24 | 99 % |
| SC25 - Projected Sums by kuraban (on 25. November 2022, 09:32) | 22 | 96 % |
| Pleiades (S-Cell Mean Mini Sudoku) by Ambrose (on 6. January 2023, 18:29) | 17 | 96 % |
| The Knights Who Say "Negator" by Scojo (on 17. September 2023, 06:41) | 23 | 99 % |
| Pam Li arrow or rail map? by palpot (on 31. January 2024, 17:38) | 30 | 92 % |
| Prime Pairings by MSDOS (on 1. June 2024, 09:33) | 21 | 94 % |
| Take More U-Turns by Black_Doom (on 30. June 2024, 18:39) | 64 | 96 % |
| 90's nostalgia by aqjhs (on 12. September 2024, 17:04) | 24 | 93 % |
