(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 | |
|---|---|---|---|
 | Tinsel Box by starwarigami (on 28. December 2023, 09:48) | 29 |  96 % |
| Global entropy by asdfg (on 8. December 2024, 09:16) | 37 | 90 % |
| Pointer Arrow Whisper Loop by yttrio (on 14. December 2024, 01:49) | 86 | 98 % |
| Ascending Starters Sudoku, 2025 by clover (on 1. January 2025, 10:47) | 31 | 94 % |
| Crimson weathercock by NicoD (on 26. April 2025, 05:30) | 63 | 91 % |
| Triumvirate by SamuPiano (on 23. September 2025, 15:44) | 34 | 91 % |
| Sequential Killer Sudoku by SenatorGronk (on 3. August 2020, 15:22) | 55 | 99 % |
| Shade Some More Sum Lines by Xendari (on 23. August 2023, 07:51) | 53 | 98 % |
| Dutch Flat Mates (Deconstruction X-Sums) (with Palpot) by Flinty (on 5. February 2025, 11:30) | 62 | 97 % |
| ABC-Box mit Hochhauskern (2) by ibag (on 3. July 2013, 08:05) | 65 | 99 % |
| Aquarium Sudoku by Sam Knott (on 20. June 2020, 13:07) | 26 | 93 % |
| Odd Trios Killer Sudoku by Quarterthru (on 19. September 2020, 12:00) | 26 | 99 % |
| Directions by SudokuExplorer (on 23. December 2021, 00:00) | 94 | 98 % |
| The Box by FryTheGuy (on 2. November 2021, 02:22) | 24 | 92 % |
| Hopscotch (Remix) by Nordy (on 3. September 2022, 08:00) | 44 | 95 % |
| Mayfair (Anti-King Region Sum Lines) by Xendari (on 8. November 2022, 08:22) | 27 | 97 % |
| Peaucellier-Lipkin by Palfly Kampling (on 22. July 2023, 05:20) | 26 | 97 % |
| Corner Prison by Prof.Dori (on 7. November 2023, 10:23) | 214 | 95 % |
| Manifold by Oddlyeven (on 28. April 2024, 15:43) | 51 | 97 % |
| Hungry Rabbit in the Fog by MCMCHammer (on 18. July 2025, 13:18) | 109 | 97 % |
