(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 | |
|---|---|---|---|
 | Zeltplatz im Zauberwald by SilBer (on 21. November 2010, 20:33) | 50 |  96 % |
| 10-in-9 sandwich sudoku by Nylimb (on 26. March 2020, 10:16) | 50 | 98 % |
| Geometry Exam #3 by Blashyrkh (on 7. August 2023, 19:46) | 59 | 94 % |
| Magic Matryoshka by Nahileon (on 9. July 2025, 17:18) | 53 | 97 % |
| Hidden Pentominoes Killer/Little Killer Sudoku by MagnusJosefsson (on 6. May 2021, 13:07) | 47 | 98 % |
| Pentominous U-Bahn (Warm-up #2) by KNT (on 15. November 2024, 09:15) | 50 | 100 % |
| The Final Shot: Four Corners 4 (Renban Arrow X) by tallcat (on 7. January 2022, 04:45) | 49 | 94 % |
| Yin × Yang = ? by SparkNights (on 9. September 2023, 04:00) | 47 | 95 % |
| Schrödinger Somedoku by gdc (on 7. May 2024, 12:35) | 98 | 98 % |
| Renban Skyscrapers by Florian Wortmann (on 26. June 2021, 13:41) | 43 | 92 % |
| Sum Thing Irregular by tallcat (on 3. November 2022, 19:41) | 48 | 95 % |
| The Arkenstone by Blobz (on 11. November 2022, 16:00) | 54 | 97 % |
| Right Twice a Day by JeffWajes (on 11. August 2025, 05:39) | 50 | 96 % |
| Mirrors by jovi_al (on 9. June 2021, 06:25) | 97 | 98 % |
| 58 by Qodec (on 10. October 2020, 16:34) | 50 | 97 % |
| Anti-Knight Killer Sudoku by SudokuExplorer (on 18. November 2021, 00:00) | 51 | 94 % |
| Build Your Own Region Sums by Jay Dyer (on 23. January 2022, 20:27) | 42 | 99 % |
| Angels by goodcity (on 8. October 2023, 18:03) | 48 | 93 % |
| Equally Mad (Dynamic FoW) by gdc (on 13. August 2025, 11:40) | 54 | 94 % |
| Rätselwochenende: Table for Four - Battleship by uvo (on 26. November 2014, 16:40) | 39 | 94 % |
