(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 | |
|---|---|---|---|
 | That's Sum Slithering by andreasv (on 16. April 2022, 08:56) | 38 |  97 % |
| Trust Me, I'm Lying by Chefofdeath (on 23. June 2022, 02:39) | 35 | 93 % |
| Hedge Maze by dennischen (on 20. May 2024, 10:10) | 32 | 91 % |
| Yin Yang X-sums by flutchman (on 6. September 2025, 15:35) | 39 | 94 % |
| Japanische Krypto-Summen-Trilogie (3) by ibag (on 31. December 2013, 07:00) | 70 | 99 % |
| Kakuro ('Plaza') by PixelPlucker (on 17. June 2021, 05:41) | 70 | 95 % |
| Four Corner Shots by noswald (on 25. May 2024, 18:28) | 47 | 95 % |
| Anti-Chess by EricRathbun (on 1. March 2024, 18:15) | 67 | 93 % |
| Tapa-Berührungsrundweg by usp (on 16. July 2014, 00:00) | 65 | 98 % |
| Normal Lunchbox by Undar_Beyond (on 14. May 2020, 11:26) | 66 | 95 % |
| Waben Summenkropki Invers und knapp daneben by Luigi (on 3. February 2010, 14:09) | 48 | 96 % |
| 24 Rätsel in 24 Stunden (Teil 14) - Fillomino by Zzzyxas (on 24. June 2017, 13:24) | 84 | 92 % |
| Wichtel 2019 (3): Die U-Bahn unter dem Geschenkelager by wichtel (on 9. July 2020, 20:01) | 49 | 100 % |
| Between the Little Killers by Stavros96 (on 25. August 2020, 12:08) | 50 | 93 % |
| X-Sum Arrows by Phistomefel (on 29. December 2020, 09:35) | 61 | 99 % |
| Slices by Joseph nehme (on 31. July 2021, 12:43) | 46 | 96 % |
| Barnyard Mouse - purpl Collab by the_cogito (on 17. December 2021, 16:11) | 21 | 95 % |
| Parity Arrows by Jay Dyer (on 22. January 2022, 11:54) | 20 | 94 % |
| Hex 2: Regular Hexagons, Irregular Sudoku by mathpesto (on 8. June 2022, 22:53) | 23 | 94 % |
| Sum Line Sudoku #1 by Phistomefel (on 1. October 2022, 10:02) | 158 | 97 % |
