(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 | |
|---|---|---|---|
 | did you say walkies!? by aqjhs (on 27. June 2025, 09:27) | 20 |  98 % |
| Japanische Summen mit Hochhauskern - gründlich daneben by ibag (on 27. March 2014, 00:00) | 58 | 100 % |
| Zum Geburtstag by Uhu (on 9. July 2017, 00:00) | 42 | 98 % |
| Chained Killer Sudoku by Shinya (on 12. January 2020, 23:22) | 44 | 93 % |
| Nexus by udukos (on 12. June 2021, 01:00) | 46 | 98 % |
| Friendly Indexing Miracle by thoughtbyte (on 5. June 2023, 18:29) | 43 | 95 % |
| Meidjuluk Fillomino Permaculture by Agent (on 27. June 2023, 09:00) | 82 | 98 % |
| Colour Wheel (Colourful Killers, Rotational Pairs) by The Book Wyrm (on 18. May 2024, 00:55) | 35 | 95 % |
| Dedicated to wisty by Myxo (on 21. January 2025, 14:25) | 32 | 94 % |
| Purple Archery Arrows by antiknight (on 9. October 2022, 17:25) | 63 | 95 % |
| Too hot to hoot! - A Thermo Palindrome Sudoku by Philipp Huber (on 18. August 2020, 19:39) | 27 | 98 % |
| Tilted Mirror - Palindrome Killer Sudoku by Tyrgannus (on 27. March 2021, 05:26) | 25 | 98 % |
| Wichtel 2020 (7): Ärger in der Wichtelwerkstatt by wichtel (on 15. September 2021, 20:20) | 22 | 100 % |
| Surround Set by PrimeWeasel (on 11. February 2022, 12:12) | 22 | 98 % |
| The final test (Deconstruction/Killer/Anti-Knight/Connect the dots) by dumediat (on 30. December 2022, 03:17) | 23 | 100 % |
| Renban Circus by JeffWajes (on 2. September 2024, 18:54) | 57 | 95 % |
| Rowena and Colin by Mad-Tyas (on 29. August 2025, 16:38) | 23 | 93 % |
| Even Lighting by Jay Dyer (on 15. February 2023, 23:02) | 65 | 97 % |
| Build Your Own Killer: Criminal Mind by Playmaker6174 (on 3. March 2022, 18:07) | 41 | 100 % |
| MIA by zetamath (on 24. May 2022, 16:03) | 96 | 98 % |
