(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 | |
|---|---|---|---|
 | Numbered Sandwich Counts by RockyRoer (on 2. August 2022, 13:57) | 33 |  96 % |
| Lightning Crashes by XeonRisq (on 23. February 2023, 04:00) | 34 | 92 % |
| Careful with that hook, Emmett ! [S-Cell Sudoku] by Christounet (on 1. March 2023, 15:12) | 63 | 95 % |
| Guidance by Jagga (on 1. July 2023, 20:07) | 31 | 93 % |
| Instructionless by dennischen (on 29. July 2023, 04:44) | 29 | 95 % |
| Mystery Boxes by Sumanta(ANU) (on 21. September 2023, 15:45) | 30 | 90 % |
| Tinsel Box by starwarigami (on 28. December 2023, 09:48) | 29 | 96 % |
| 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 % |
| Splitting hairs (Equal split lines) by Lizzy01 (on 13. April 2025, 17:40) | 34 | 94 % |
| Crimson weathercock by NicoD (on 26. April 2025, 05:30) | 63 | 91 % |
| Triumvirate by SamuPiano (on 23. September 2025, 15:44) | 34 | 91 % |
| Corner Prison by Prof.Dori (on 7. November 2023, 10:23) | 216 | 95 % |
| 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 % |
| Tenfinity by ThePedallingPianist (on 23. November 2025, 18:45) | 54 | 95 % |
| 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 % |
