(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 | |
|---|---|---|---|
 | Battlefield Sudoku #4: Knights! by Big Tiger (on 23. June 2020, 04:08) | 28 |  97 % |
| Overlapping Notes (Double digit thermometer sudoku) by Aspartagcus (on 28. August 2021, 21:13) | 29 | 98 % |
| Patchwork by steelwool (on 11. October 2022, 18:00) | 29 | 94 % |
| Waterworld by Palfly Kampling (on 16. June 2023, 02:37) | 29 | 92 % |
| Quintessence [Pentominous Fillomino] by MicroStudy (on 29. June 2023, 21:28) | 73 | 97 % |
| Whirlwind by SamuPiano (on 2. January 2024, 22:00) | 61 | 98 % |
| Diagonal-Windoku by ibag (on 29. December 2011, 20:09) | 64 | 95 % |
| Binary Sudoku 11 by stephane.bura (on 26. April 2020, 23:39) | 18 | 96 % |
| Thermal Arrow Killer X by primovera (on 15. January 2021, 01:29) | 21 | 94 % |
| Whispers in the Night by ___ (on 13. June 2021, 05:24) | 52 | 96 % |
| Chromatic Whispers by Nahileon (on 28. September 2021, 19:32) | 37 | 94 % |
| Ramparts by SSG (on 11. October 2021, 12:15) | 17 | 90 % |
| Only Thermos by Mesmer (on 20. October 2021, 18:10) | 48 | 94 % |
| [New Constraint] Entropy Sudoku by Mad-Tyas (on 3. December 2021, 05:28) | 122 | 92 % |
| Phone in your Crossword Puzzle By Olima and PanthChesh by panthchesh (on 8. March 2022, 04:09) | 15 | 90 % |
| Rooks are Better by meggen033 (on 23. September 2022, 09:43) | 62 | 95 % |
| Passing Storm (Antiknight Arrows) by Florian Wortmann (on 2. October 2022, 16:19) | 71 | 95 % |
| Pleiades (S-Cell Mean Mini Sudoku) by Ambrose (on 6. January 2023, 18:29) | 13 | 94 % |
| Antarctic Expedition (Icebarn Hybrid) by sfushidahardy (on 1. July 2024, 23:01) | 18 | 90 % |
| 90's nostalgia by aqjhs (on 12. September 2024, 17:04) | 18 | 90 % |
