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 | |
|---|---|---|---|
![]() | The Vs by ademjaz (on 12. October 2022, 00:19) | 58 | ![]() 93 % |
![]() | Reflections by EricRathbun (on 1. July 2024, 15:13) | 55 | ![]() 96 % |
![]() | Cradle by Xenonetix (on 28. October 2024, 22:55) | 56 | ![]() 92 % |
![]() | Whispers of Doom 4 by NurglesGift (on 12. December 2025, 18:56) | 58 | ![]() 94 % |
![]() | Ringban by Ridhwan (on 1. March 2023, 07:21) | 66 | ![]() 91 % |
![]() | Anti-King Thermo Sudoku by Blashyrkh (on 26. January 2024, 16:35) | 64 | ![]() 95 % |
![]() | Burrows by jovi_al (on 18. July 2021, 03:38) | 74 | ![]() 96 % |
![]() | Orchid by mathpesto (on 6. September 2025, 19:03) | 76 | ![]() 97 % |
![]() | Adaptation by mathpesto (on 18. January 2025, 17:49) | 81 | ![]() 98 % |
![]() | 010-er Hochhaus mit PS by julius64 (on 24. December 2010, 00:01) | 44 | ![]() 90 % |
![]() | Wichtelkalender 2013 - Juli by ibag (on 1. July 2013, 00:00) | 49 | ![]() 98 % |
![]() | Table for Four - Easy as Pentomino by uvo (on 19. August 2014, 12:43) | 32 | ![]() 92 % |
![]() | 10-in-9 little killer sudoku by Nylimb (on 22. April 2020, 03:31) | 32 | ![]() 97 % |
![]() | Stacked Sandwiches Sudoku by stephane.bura (on 8. July 2020, 08:03) | 54 | ![]() 95 % |
![]() | Prime Killer Sudoku by udukos (on 25. July 2020, 17:54) | 47 | ![]() 95 % |
![]() | Multi-Way Skyscraper Sudoku by SudokuExplorer (on 18. September 2020, 16:00) | 25 | ![]() 97 % |
![]() | Unique Aquarium Sudoku by Sam Knott (on 22. September 2020, 15:17) | 55 | ![]() 99 % |
![]() | Blackjack Sudoku-It's all 21 by bigger (on 21. January 2021, 21:21) | 24 | ![]() 94 % |
![]() | U-Bahn 3 by Dandelo (on 31. January 2021, 18:59) | 42 | ![]() 96 % |
![]() | 33 magnificent dots by PetLov (on 31. March 2021, 10:29) | 35 | ![]() 99 % |