(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 | |
|---|---|---|---|
 | No Idea by rysmyth240 (on 11. April 2021, 17:13) | 80 |  93 % |
| These Two Equal These Two by EricRathbun (on 1. February 2026, 00:30) | 41 | 94 % |
| Revenge of Triad by Tyrgannus (on 18. September 2021, 06:57) | 42 | 97 % |
| Pastiche by zetamath (on 4. November 2022, 00:18) | 99 | 95 % |
| Liar Japanese Sums #4 - Ciphered Yin Yang by Niverio (on 1. February 2023, 11:22) | 54 | 99 % |
| Ambiguous Slitherlink by Agent (on 28. April 2024, 09:00) | 60 | 98 % |
| Chameleon [Antiknight Series] by wisty (on 26. November 2024, 15:35) | 73 | 90 % |
| Roller Coaster Fillomino #2 (9x9) by Jesper (on 21. April 2021, 09:08) | 65 | 100 % |
| Masyudoku - Sudoku / Masyu Hybrid by Mr.Menace (on 2. November 2022, 21:14) | 64 | 98 % |
| Candles in the Dark by Dave Sandwich (on 22. November 2022, 23:44) | 71 | 92 % |
| Coupled Up by IcyFruit (on 13. February 2024, 17:14) | 71 | 92 % |
| Imperfect Miracle by Las4one (on 2. August 2025, 02:00) | 78 | 95 % |
| Point Proven by oskode (on 21. October 2025, 09:40) | 90 | 97 % |
| Kreuzzahlrätsel (4) by berni (on 21. October 2010, 11:57) | 42 | 91 % |
| Wichtel 2018 (8): Zahlenweihnachtsbaum by wichtel (on 24. December 2019, 12:08) | 31 | 96 % |
| 6x6 Chaos Construction: Boundary N-Sums (墨子) by SudokuExplorer (on 27. April 2021, 01:00) | 30 | 94 % |
| Renban X-sums sudoku by udukos (on 20. July 2021, 19:45) | 48 | 100 % |
| Frankenstein by PotatoHead21 (on 6. November 2021, 13:40) | 30 | 96 % |
| Median Quads by RockyRoer (on 13. November 2021, 05:07) | 21 | 92 % |
| Coordinate Arrows (Sudoku) by Piatato (on 13. February 2022, 18:17) | 138 | 96 % |
