(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 | |
|---|---|---|---|
 | Killer Shikoku by the_cogito (on 9. March 2022, 00:16) | 62 |  96 % |
| Ocean by kolot (on 15. August 2021, 07:58) | 39 | 98 % |
| Assorted Sandwiches Sudoku by stephane.bura (on 15. June 2020, 14:37) | 22 | 95 % |
| arROw SudOkU rEduX by filuta (on 20. April 2021, 13:49) | 18 | 93 % |
| Y Are We Whispering? by glum_hippo (on 18. September 2021, 04:12) | 36 | 94 % |
| Stepwell by mormagli (on 14. May 2022, 07:17) | 20 | 93 % |
| Sum Kind of Maze by mormagli (on 28. July 2022, 19:24) | 18 | 92 % |
| Japanese Sums Nurikabe Arrows (9x9) by Xendari (on 1. January 2023, 08:55) | 16 | 95 % |
| Hybrid Star Battle Series (017) - Easy as ABC by BenceJoful (on 6. May 2023, 01:45) | 18 | 97 % |
| Is 4 a Low Digit? by blackjackfitz (on 30. August 2023, 03:23) | 24 | 92 % |
| Rhizome (Fillomino/Landvermessung/Irrwisch) by dumediat (on 13. September 2023, 13:06) | 16 | 96 % |
| Deconstruction of Whisper Tree (11x11) by SparkNights (on 4. February 2024, 07:05) | 40 | 97 % |
| Schrödinger's Knights by lepton (on 9. March 2024, 11:50) | 17 | 92 % |
| Dust Torus (Black Hole) by heliopolix (on 14. September 2024, 00:00) | 22 | 98 % |
| Canyonlands (A38 + Rassi Silai) by sfushidahardy (on 16. March 2025, 17:07) | 17 | 93 % |
| Tentropic Terrier by Scojo (on 11. June 2025, 20:06) | 19 | 97 % |
| Directed Entropy by egubachu (on 11. June 2025, 22:11) | 20 | 91 % |
| HeX-Sums by qoala (on 13. June 2025, 09:00) | 19 | 90 % |
| Chaos Construction: Numbered Regions #1 by Jesper (on 24. September 2022, 15:15) | 168 | 100 % |
| Bouquet by Myxo (on 15. September 2023, 10:41) | 92 | 98 % |
