(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 | |
|---|---|---|---|
 | Squishy Deconstruction by Oddlyeven (on 8. June 2024, 14:52) | 17 |  95 % |
| Deconstruction: X-Sums by Jesper (on 21. March 2022, 10:26) | 109 | 100 % |
| Archa by zetamath (on 10. January 2022, 06:28) | 91 | 100 % |
| Angebranntes Kropki by Luigi (on 12. May 2011, 14:55) | 34 | 91 % |
| Stingray by zetamath (on 23. June 2021, 19:36) | 39 | 92 % |
| The Final Move by kolot (on 28. October 2021, 05:01) | 37 | 98 % |
| Down for the Count by juggler (on 31. October 2024, 19:06) | 36 | 93 % |
| Wichtelkalender 2013 – September by Susie (on 1. September 2013, 00:00) | 39 | 90 % |
| Pencil puzzle sudoku hybrid series #3 - Aqre arrow sudoku by Aspartagcus (on 17. November 2020, 17:05) | 21 | 97 % |
| Fifth Floor Penthouses by SSG (on 8. July 2022, 07:32) | 22 | 91 % |
| All Things Being Equal by actinide (on 6. August 2022, 14:59) | 40 | 95 % |
| Counterclockwise Killer by bodemeister (on 11. February 2023, 15:26) | 19 | 92 % |
| Double U is actually an S by ademjaz (on 28. February 2023, 00:08) | 23 | 92 % |
| Summer Snakes by yttrio (on 25. August 2023, 22:28) | 59 | 97 % |
| 4 Choose 2 by Prof.Dori (on 28. March 2024, 14:39) | 22 | 97 % |
| Slitherbahn by KNT (on 5. August 2024, 09:00) | 37 | 100 % |
| Chaos Construction: Ariadne's Pet Dinosaur by Myxo (on 24. June 2023, 13:08) | 101 | 94 % |
| Hurra für Zafer! by Richard (on 30. August 2011, 00:00) | 57 | 97 % |
| Japanische Koralle 2358 by Uhu (on 30. December 2016, 19:00) | 55 | 98 % |
| Sudokurotto by Phistomefel (on 15. September 2021, 07:39) | 117 | 99 % |
