(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 | |
|---|---|---|---|
 | Three is a Crowd Sudoku by rk1970 (on 22. April 2020, 09:26) | 40 |  95 % |
| Wichtel 2019 (4): Unvollendet ausgegraben by wichtel (on 17. August 2020, 20:10) | 24 | 99 % |
| 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) | 27 | 94 % |
| Revenge of the Hash (Irregular Thermo Sudoku) by lavaloid (on 9. May 2021, 11:00) | 13 | 95 % |
| Steering Wheel (Classic) by SudokuExplorer (on 14. August 2021, 02:00) | 60 | 91 % |
| Renban/Skyscrapers Sudoku by MagnusJosefsson (on 11. September 2021, 13:47) | 26 | 95 % |
| Battle With The Archers 21: The Order of Three Worlds by Playmaker6174 (on 19. November 2021, 16:56) | 43 | 98 % |
| SiXteen by djorr (on 22. April 2022, 14:00) | 14 | 95 % |
| Chaotic Measures by Andrewsarchus (on 1. May 2022, 08:18) | 27 | 95 % |
| Self-determination 2 by stephane.bura (on 3. November 2022, 14:20) | 17 | 96 % |
| Nun Gimel Hay Shin - A Chanukah Sudoku by Mojo872 (on 15. December 2022, 06:12) | 59 | 94 % |
| Checkered (Psycho Look-and-Say/German whispers/Renban) by dumediat (on 29. August 2023, 16:54) | 13 | 95 % |
| K2 (Anti-diagonal arrow sudoku) by Qodec (on 28. October 2023, 17:22) | 71 | 97 % |
| German Summing Doppelganger by feethy (on 3. March 2024, 18:40) | 11 | 100 % |
| Three's a Crowd by XeonRisq (on 17. July 2024, 02:00) | 11 | 91 % |
| Gemstones by Scojo (on 17. July 2024, 21:29) | 16 | 91 % |
| Widdershins by kuraban (on 25. August 2024, 13:01) | 15 | 93 % |
| Blue, white and black 2.0 by Visumation (on 18. October 2024, 11:52) | 28 | 94 % |
| Stacked - Arrow Sudoku by Mr.Menace (on 6. July 2021, 20:51) | 48 | 98 % |
