(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 | |
|---|---|---|---|
 | Chaotic Chess by Belamis (on 30. May 2025, 22:09) | 70 |  96 % |
| King's Siege by Sniglett (on 10. March 2024, 23:05) | 46 | 96 % |
| Rank Up 10 - Chaos Construction by ThePedallingPianist (on 27. July 2024, 23:34) | 45 | 98 % |
| Richard's Bouncy Castle Birthday Party by Lizzy01 (on 23. February 2025, 00:55) | 43 | 97 % |
| Twin Killer Sudoku by Richard (on 23. January 2009, 10:36) | 142 | 95 % |
| Far Far Away (Doubler Remote Sums Sudoku) by Agent (on 11. May 2024, 09:00) | 102 | 98 % |
| Lake Trip by TotallyNormalCat (on 12. February 2021, 17:30) | 68 | 98 % |
| Untitled Killer by Neb (on 9. June 2025, 15:00) | 128 | 98 % |
| Residuum by NicoD (on 2. September 2025, 05:30) | 65 | 97 % |
| Cryptic News (NEWS birthday puzzle) by sujoyku (on 23. February 2026, 18:27) | 74 | 98 % |
| Duplicates Somedoku by blackjackfitz (on 2. March 2024, 20:42) | 156 | 98 % |
| Entropy Minimalism by Mad-Tyas (on 10. January 2022, 13:01) | 85 | 96 % |
| Empty Circles by Qodec (on 20. October 2023, 17:32) | 85 | 95 % |
| Roller Coaster by Uhu (on 2. November 2016, 13:21) | 77 | 98 % |
| Mystery Killer Triplets (Little Killer Sudoku) by SudokuExplorer (on 8. August 2020, 03:00) | 21 | 98 % |
| Cage Escape (Thermo Killer) by Stavros96 (on 23. February 2021, 10:44) | 46 | 97 % |
| Speaking to the Atmosphere by EliasKar (on 28. April 2021, 13:28) | 23 | 92 % |
| Quadiagonal by Tyrgannus (on 29. May 2021, 21:19) | 47 | 91 % |
| Little Killer Between Sudoku by SudokuExplorer (on 24. August 2021, 02:00) | 36 | 96 % |
| Thermo x-sums sudoku by Aspartagcus (on 21. January 2022, 08:04) | 23 | 97 % |
