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 | |
|---|---|---|---|
![]() | Myriapods by marty_sears (on 17. August 2025, 00:14) | 301 | ![]() 97 % |
![]() | 3 Star Star Battle: Skirmish in the Horsehead Nebula by Thorsby (on 3. September 2020, 00:01) | 48 | ![]() 98 % |
![]() | Kill Between The Lines by Djmelee3000 (on 29. September 2020, 02:39) | 45 | ![]() 93 % |
![]() | Arrow Sudoku by KNT (on 17. April 2022, 05:46) | 100 | ![]() 96 % |
![]() | Embark (Fog of war/Deconstruction/Killer/Yajilin) by dumediat (on 21. January 2023, 13:50) | 158 | ![]() 97 % |
![]() | EXit Strategy by riffclown (on 17. May 2023, 13:35) | 100 | ![]() 93 % |
![]() | Maximus Unique by Klvsched (on 24. June 2024, 14:00) | 112 | ![]() 95 % |
![]() | Froschteich by Myxo (on 25. August 2024, 15:01) | 48 | ![]() 94 % |
![]() | Frohe Weihnachten! by Richard (on 23. December 2011, 12:00) | 57 | ![]() 95 % |
![]() | Ménage à Trois by Die Hard (on 5. December 2023, 05:16) | 59 | ![]() 95 % |
![]() | Happy Anniversary Mum & Dad! by ThePedallingPianist (on 26. September 2024, 23:34) | 62 | ![]() 96 % |
![]() | Colours in the (k)night XX by Villse (on 22. December 2025, 14:23) | 135 | ![]() 95 % |
![]() | Highball by MSDOS (on 5. May 2025, 21:45) | 193 | ![]() 96 % |
![]() | Angel by zetamath (on 8. August 2025, 19:50) | 92 | ![]() 96 % |
![]() | Rätselwochenende: Table for Four - Paint it Black Tetrominos by uvo (on 26. November 2014, 16:40) | 40 | ![]() 93 % |
![]() | Diagonal Killer Sudoku by Selsted (on 2. August 2020, 15:10) | 41 | ![]() 92 % |
![]() | Little Killer X Sudoku by Willy Wonka (on 10. August 2020, 11:02) | 69 | ![]() 97 % |
![]() | Sub-Zero Thermometers by clover (on 20. August 2020, 22:35) | 17 | ![]() 98 % |
![]() | Mini Killers by Aspartagcus (on 6. September 2020, 20:30) | 27 | ![]() 96 % |
![]() | Odd-Even Sandwich Sudoku by stephane.bura (on 17. September 2020, 20:00) | 17 | ![]() 95 % |