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 | |
|---|---|---|---|
![]() | Embedded Sandwich Sudoku - Taco Bowl by DiMono (on 8. March 2021, 06:41) | 40 | ![]() 97 % |
![]() | Put a ring on it (if you like it) by Ali M (on 26. March 2024, 16:32) | 50 | ![]() 94 % |
![]() | Kakuro-Koralle by ibag (on 5. September 2013, 23:55) | 79 | ![]() 96 % |
![]() | Zeroth Law of Chromodynamics by twototenth (on 26. April 2021, 13:08) | 91 | ![]() 97 % |
![]() | Dreams by Zibl (on 15. November 2025, 19:06) | 92 | ![]() 98 % |
![]() | LM Gapped Kakuro by yureklis (on 3. January 2011, 23:50) | 90 | ![]() 96 % |
![]() | Product Ltd. by BoaConstructor (on 30. July 2020, 12:57) | 53 | ![]() 97 % |
![]() | Fully Booked [Numbered Rooms Fillomino] by MicroStudy (on 26. January 2024, 12:26) | 105 | ![]() 97 % |
![]() | /4 /5 by Nahileon (on 18. March 2022, 11:03) | 59 | ![]() 99 % |
![]() | Fifteen All by Phurba (on 10. June 2024, 12:54) | 62 | ![]() 90 % |
![]() | Streuung by Myxo (on 24. July 2024, 13:27) | 65 | ![]() 93 % |
![]() | Renban -Kakuro 1-10 / 2 by julius64 (on 4. May 2011, 21:18) | 68 | ![]() 94 % |
![]() | Scattered X-Sums Sudoku (2) by Richard (on 13. June 2014, 12:00) | 77 | ![]() 93 % |
![]() | Pincers (Diagonal constraint killer sudoku) by sujoyku (on 10. September 2023, 09:32) | 105 | ![]() 95 % |
![]() | Benebelte Nachbarschaft (FOW) by Myxo (on 19. August 2023, 05:25) | 384 | ![]() 96 % |
![]() | Rundweg auf der Kleinschen Flasche by flooser (on 14. November 2009, 12:52) | 54 | ![]() 91 % |
![]() | Ausgedehnte Mittagspause by Richard (on 26. February 2010, 12:00) | 67 | ![]() 97 % |
![]() | RiesenRenbanKropki by Richard (on 26. March 2010, 12:00) | 70 | ![]() 90 % |
![]() | Treppen (4) by BFaw (on 28. August 2012, 09:00) | 25 | ![]() 94 % |
![]() | Adventsportale, Teil 2 by pirx (on 9. December 2018, 12:00) | 34 | ![]() 97 % |