(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 | |
|---|---|---|---|
 | Yin-Yang Whispers by Scruffamudda (on 4. May 2025, 09:46) | 40 |  93 % |
| Foundations by Andrewsarchus (on 20. June 2025, 22:13) | 37 | 97 % |
| Fare thee well, Miss Carousel by Phistomefel (on 12. July 2024, 17:38) | 130 | 98 % |
| Killer Sudoku #2 ('ZooZ') by PixelPlucker (on 31. October 2021, 13:55) | 45 | 91 % |
| Numbered Corridors by RockyRoer (on 7. July 2022, 13:25) | 49 | 97 % |
| Halligen by KNT (on 8. January 2023, 07:48) | 43 | 99 % |
| Misdirection by MicroStudy (on 24. May 2023, 15:31) | 44 | 95 % |
| Sprawling by Xenonetix (on 14. April 2024, 01:01) | 42 | 97 % |
| Philly by zetamath (on 8. July 2024, 01:14) | 48 | 94 % |
| Japanese Sums #1: Vanilla by Myxo (on 19. April 2023, 16:00) | 101 | 98 % |
| Six-pack Linked Sudokus #2 by Genomico (on 4. October 2020, 16:49) | 57 | 98 % |
| Quiet, please! (renban whispers sudoku) A.k.a. "The Pipe" by Lizzy01 (on 18. August 2022, 20:51) | 52 | 98 % |
| Gee, Officer Kropki by EdTheAlchemist (on 18. November 2025, 13:08) | 57 | 96 % |
| Magnificent Mansion (with oskode) by Calvinball (on 19. April 2026, 23:38) | 51 | 96 % |
| Squares of Parity Sudoku by Richard (on 21. December 2022, 06:00) | 60 | 95 % |
| Snakomino [Level #1] by Christounet (on 1. February 2023, 22:17) | 63 | 99 % |
| Honk! by Nahileon (on 12. February 2023, 22:14) | 62 | 95 % |
| The Clues, the Whole Clues, and Nothing but the Clues. by Abdul the Killer (on 23. July 2024, 12:34) | 74 | 97 % |
| Left Turn At Albuquerque by ChinStrap (on 23. September 2025, 17:16) | 83 | 97 % |
| Jubiläumsrätsel - 4 Jahre Rätselportal by Richard (on 1. November 2012, 00:00) | 89 | 98 % |
