(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 | |
|---|---|---|---|
 | RemotelyEntropic by Palfly Kampling (on 27. May 2023, 18:52) | 28 |  95 % |
| Islands 2: Global Ocean by SamuPiano (on 13. July 2023, 03:17) | 86 | 96 % |
| Chaos Construction: X-Sums and Lines by KNT (on 2. April 2022, 19:42) | 93 | 96 % |
| Fibonaccis Fillo-Tapa (Permakultur) by usp (on 4. August 2014, 12:00) | 29 | 94 % |
| Wichtel 2018 (4): Ein spezielles Weihnachtsmarktgelände by wichtel (on 15. November 2019, 08:12) | 53 | 100 % |
| Timid Dominoes by Genomico (on 15. August 2020, 02:13) | 31 | 99 % |
| "Thermo" ;) by apiyo (on 11. February 2021, 05:51) | 35 | 91 % |
| Mean, Median, and Mode by RockyRoer (on 27. May 2021, 00:00) | 28 | 97 % |
| The Grand Illusion by HalfBakedLunatic (on 14. May 2023, 15:03) | 33 | 96 % |
| [TSL] damasosos92 would be sad if i don't publish this by Myxo (on 26. October 2024, 14:30) | 26 | 95 % |
| Unique Under the Fog 7.0 by Visumation (on 1. June 2025, 15:57) | 70 | 90 % |
| La Grande Illusion by Kafkapharnaum (on 23. December 2025, 01:29) | 28 | 91 % |
| Anti-Knight Killer Sudoku by Willy Wonka (on 26. July 2020, 04:56) | 91 | 95 % |
| Archer's Gate by SudokuExplorer (on 20. July 2021, 02:00) | 61 | 97 % |
| Twin Killer Sudoku by Richard (on 23. January 2009, 10:36) | 139 | 95 % |
| Battlefield Sudoku #3: Uncharted by Big Tiger (on 15. June 2020, 02:07) | 26 | 94 % |
| Catch the fish (Arrows) by abed hawila (on 12. April 2021, 12:05) | 27 | 95 % |
| Cithara by BIGfoot (on 2. November 2021, 15:38) | 30 | 91 % |
| Xandwich by Qodec (on 4. January 2022, 01:14) | 53 | 96 % |
| Chaos Construction: 2nd Region X-Sums #1 (8x8) by Jesper (on 3. April 2022, 16:03) | 78 | 100 % |
