(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 Corners are Even Double - Double Arrow Even/Odd Sudoku by Mr.Menace (on 29. August 2022, 20:08) | 26 |  92 % |
| Sprawl by jovi_al (on 22. September 2022, 20:27) | 23 | 95 % |
| Meidjuluk II (N=25) by glum_hippo (on 1. June 2023, 00:00) | 47 | 99 % |
| Loop with a Coral Infestation by KNT (on 20. August 2023, 20:00) | 24 | 100 % |
| Birefringence by Jay Dyer (on 25. August 2023, 20:46) | 55 | 95 % |
| I Made A Pencil Puzzle: Fillomino (12x12) by Playmaker6174 (on 5. November 2023, 12:00) | 28 | 93 % |
| Regionometers by ThePedallingPianist (on 20. February 2024, 13:20) | 24 | 95 % |
| Broken Secrets by TotallyNormalCat (on 2. June 2021, 07:00) | 60 | 98 % |
| Meidjuluk Fillomino Permaculture by Agent (on 27. June 2023, 09:00) | 76 | 98 % |
| Balanced Chaos by fritzdis (on 29. November 2022, 16:24) | 107 | 97 % |
| LM 2016 - Spätfolgen: Sternenhimmel-Japanische Summen by ibag (on 15. August 2016, 20:13) | 42 | 99 % |
| Pentopia Rundweg II by tuace (on 22. April 2019, 09:55) | 50 | 99 % |
| Unbekannte Bahnhöfe by Dandelo (on 13. August 2021, 18:23) | 14 | 100 % |
| Wichtel 2021 (7): In der Weihnachtsbäckerei by wichtel (on 4. October 2022, 21:02) | 14 | 100 % |
| My cup runneth over intensely by Fool on Hill (on 19. August 2022, 13:29) | 19 | 94 % |
| Schrödinger Sudkuro by ICHTUES (on 30. October 2022, 06:00) | 45 | 97 % |
| LM-Quali 2023 Leftover: Hashiwokakero by CJK (on 12. March 2023, 20:23) | 16 | 94 % |
| Mean World Syndrome [Mean Arrow, Kropki] by Miky (on 1. May 2023, 17:29) | 34 | 96 % |
| Atlantis by Kafkapharnaum (on 26. May 2023, 23:22) | 14 | 100 % |
| Copycat Copycat by Scojo (on 24. June 2023, 04:05) | 14 | 100 % |
