(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 | |
|---|---|---|---|
 | Matching by kolot (on 15. November 2021, 05:22) | 87 |  98 % |
| Cliffs of Insanity by DarthParadox (on 27. June 2022, 00:06) | 22 | 93 % |
| Curvedoku by chameleon (on 1. July 2022, 13:23) | 23 | 100 % |
| Heavy Ominoes by Jay Dyer (on 19. May 2024, 23:48) | 47 | 97 % |
| Efflorescence [Arrows, Killer] by 3good5you (on 29. May 2024, 00:56) | 30 | 95 % |
| The Good, the Bad and the Circled (fillomino) by SkepticalMario (on 6. February 2025, 14:38) | 22 | 96 % |
| Easy as RBC - Arrows and Renbans by Laake (on 10. June 2025, 11:59) | 41 | 96 % |
| Classic Summation U-bahn by Playmaker6174 (on 6. November 2025, 06:00) | 18 | 97 % |
| Metope (Chaos Construction) by tallcat (on 9. December 2023, 08:00) | 130 | 97 % |
| 27 Killer by Florian Wortmann (on 26. February 2023, 13:14) | 89 | 96 % |
| Kaboom by mathpesto (on 25. November 2023, 13:51) | 91 | 97 % |
| The Incomplete Diamond by Niverio (on 14. July 2021, 15:19) | 41 | 95 % |
| Consecutive Sums Sudoku by SudokuExplorer (on 21. October 2021, 22:15) | 38 | 99 % |
| Rank Up 10 - Chaos Construction by ThePedallingPianist (on 27. July 2024, 23:34) | 44 | 98 % |
| Zodiac Project: Isolation by vitaminz (on 5. February 2025, 22:41) | 45 | 95 % |
| SET by ICHTUES (on 16. March 2025, 06:00) | 43 | 95 % |
| Lake Trip by TotallyNormalCat (on 12. February 2021, 17:30) | 67 | 98 % |
| Chaotic Chess by Belamis (on 30. May 2025, 22:09) | 68 | 95 % |
| Empty Circles by Qodec (on 20. October 2023, 17:32) | 82 | 95 % |
| Roller Coaster by Uhu (on 2. November 2016, 13:21) | 76 | 98 % |
