(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 | |
|---|---|---|---|
 | Challah by pieguy (on 10. November 2023, 03:30) | 46 |  91 % |
| Myriapods by marty_sears (on 17. August 2025, 00:14) | 313 | 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 % |
| Unique Killers by Yawnus (on 24. February 2023, 11:50) | 54 | 96 % |
| EXit Strategy by riffclown (on 17. May 2023, 13:35) | 100 | 93 % |
| Maximus Unique by Klvsched (on 24. June 2024, 14:00) | 112 | 95 % |
| 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 % |
| Classic Arrow Sudoku by Phistomefel (on 11. October 2020, 09:48) | 147 | 96 % |
| Highball by MSDOS (on 5. May 2025, 21:45) | 194 | 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 % |
| Glass Skyscraper Sudoku(P2) by cdwg2000 (on 25. September 2020, 07:39) | 16 | 91 % |
