(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 | |
|---|---|---|---|
 | Border skirmish (battlefield) sudoku by Nylimb (on 7. June 2020, 03:39) | 43 |  99 % |
| The Soused Snake by Big Tiger (on 30. June 2020, 02:23) | 17 | 95 % |
| DSM Qualitraining 2021: Average Arrows by Realshaggy (on 17. January 2021, 06:00) | 40 | 97 % |
| Anti-King Arrow X Killer by ICHTUES (on 21. March 2021, 06:00) | 28 | 94 % |
| Renban X-sums sudoku by udukos (on 20. July 2021, 19:45) | 47 | 100 % |
| Did someone say Mondrian? (Killer) by Chilly (on 2. August 2021, 23:27) | 16 | 91 % |
| Renban/Skyscrapers Sudoku by MagnusJosefsson (on 11. September 2021, 13:47) | 26 | 95 % |
| Baba is Anti-Knight by FryTheGuy (on 16. October 2021, 21:36) | 40 | 97 % |
| Killer Sudoku by PotatoHead21 (on 12. December 2021, 08:36) | 58 | 93 % |
| Pared Down (Parity Arrow) by tallcat (on 22. January 2022, 22:44) | 55 | 92 % |
| SiXteen by djorr (on 22. April 2022, 14:00) | 14 | 95 % |
| Thermos and Cages by Jeet Sampat (on 7. March 2022, 04:31) | 32 | 97 % |
| Knight Sweats by SlowLarry (on 21. August 2022, 16:26) | 33 | 94 % |
| The Demon Watch by Perladel (on 26. August 2022, 14:28) | 28 | 96 % |
| Falling Arrows by antiknight (on 24. December 2022, 02:44) | 89 | 94 % |
| Known Unknowns by Scruffamudda (on 6. June 2023, 10:29) | 17 | 93 % |
| What are the odds? (Parity killer/little killer) by sujoyku (on 18. August 2023, 10:15) | 42 | 94 % |
| Checkered (Psycho Look-and-Say/German whispers/Renban) by dumediat (on 29. August 2023, 16:54) | 13 | 95 % |
| The Juggler [Modular Lines, Kropki Pairs] by Malrog (on 13. March 2024, 13:03) | 27 | 94 % |
| Three's a Crowd by XeonRisq (on 17. July 2024, 02:00) | 11 | 91 % |
