(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 | |
|---|---|---|---|
 | The Fillomino Frog 2 by Die Hard (on 1. March 2025, 23:51) | 21 |  96 % |
| Doppel Arrows by Scojo (on 6. December 2025, 08:09) | 27 | 92 % |
| 2CT Appreciation (German Whispers thermometer sudoku) by Qodec (on 1. January 2024, 23:34) | 92 | 97 % |
| Chaos Zippers by Visumation (on 19. January 2025, 13:10) | 74 | 92 % |
| Mehrdeutige Rätsel - Rundweg 2 by uvo (on 22. February 2017, 10:01) | 44 | 95 % |
| Japanese Icewalk (1) by KNT (on 17. August 2025, 20:44) | 45 | 99 % |
| Uncertain Sudoku #8 - Frame or X-Sums by Feadoor (on 27. March 2020, 17:00) | 55 | 96 % |
| Catch The Zippersnake by marty_sears (on 8. January 2024, 01:41) | 129 | 97 % |
| 10-in-9 killer sudoku #4 by Nylimb (on 21. February 2020, 17:48) | 36 | 98 % |
| Silent Night by titus (on 18. December 2020, 02:06) | 25 | 90 % |
| Sandwich Cosmic Sudoku - Follow the North Galaxy by DiMono (on 27. December 2020, 21:37) | 18 | 93 % |
| Anjou by Konzert (on 21. February 2021, 22:12) | 45 | 95 % |
| The Difference Between a Cage by Mr.Goodkitteh (on 28. April 2021, 15:47) | 21 | 98 % |
| Living on the Diagonal by Sktx (on 25. May 2021, 00:10) | 19 | 97 % |
| Orderly Little Killer 3 by Strosahl (on 2. July 2021, 07:11) | 17 | 92 % |
| Cursor by ICHTUES (on 26. December 2021, 06:00) | 17 | 95 % |
| Arrowings (version 2) by kolot (on 27. January 2022, 11:30) | 19 | 93 % |
| Fire Watchers by Angelo (on 15. March 2022, 23:09) | 18 | 97 % |
| Entangled by Flywinged (on 23. August 2022, 16:23) | 22 | 90 % |
| Echo Chamber by ndsurgenor (on 26. February 2023, 11:00) | 20 | 93 % |
