(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 | |
|---|---|---|---|
 | Bushido (Star Battle Japanese Sums Fillomino) by Agent (on 6. December 2022, 09:00) | 38 |  99 % |
| Chaos Construction: Loop Sum by Phistomefel (on 8. April 2022, 18:16) | 130 | 99 % |
| Subway Roundabout by Niverio (on 21. August 2024, 22:25) | 29 | 97 % |
| Krypto-Kakuro-Koralle für pin7guin by ibag (on 6. September 2013, 00:00) | 60 | 99 % |
| Exums by Xenonetix (on 27. May 2022, 22:22) | 42 | 99 % |
| Fractional Dimension (Chaos Construction) by Chilly (on 14. June 2022, 14:33) | 48 | 98 % |
| Pinch Hitter by ViKingPrime (on 14. May 2024, 03:00) | 24 | 92 % |
| Compass Chaos Construction by Jay Dyer (on 11. March 2023, 20:08) | 58 | 99 % |
| Dutch Baby - a Snake Egg Sudoku by glum_hippo (on 13. January 2024, 07:17) | 68 | 96 % |
| 3D Killer Sudoku by SlowLarry (on 21. May 2020, 17:32) | 18 | 96 % |
| arROw SudOkU rEduX by filuta (on 20. April 2021, 13:49) | 15 | 92 % |
| Wichtel 2020 (10): Vier Wichtel, vier Viertel by wichtel (on 5. October 2021, 02:02) | 25 | 99 % |
| Arrows Anonymous by XeonRisq (on 11. March 2022, 04:00) | 12 | 98 % |
| Which Blare? by XeonRisq (on 28. August 2022, 22:00) | 15 | 92 % |
| TRICKY - Buchstabenrätsel / Letter Puzzle by DocLogic (on 16. April 2024, 15:44) | 27 | 97 % |
| Wichtels (später) Rätselsommer 2024 (10): Yingu Jam by wichtel (on 3. October 2024, 20:23) | 12 | 91 % |
| Archer's Heart by SudokuExplorer (on 5. October 2021, 00:00) | 46 | 98 % |
| Covert Confinement by SSG (on 21. January 2022, 07:01) | 38 | 97 % |
| Die Kryptos - S02E06: Summenbild Rundweg / Sudoku by tuace (on 16. March 2018, 15:10) | 39 | 100 % |
| Skyscraper^2 Sudoku by Prasanna16391 (on 5. August 2020, 13:47) | 22 | 99 % |
