(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 | |
|---|---|---|---|
 | Pentomino Sandwich by RockyRoer (on 9. January 2023, 23:42) | 17 |  97 % |
| Amicus by Andrewsarchus (on 21. August 2023, 08:43) | 42 | 95 % |
| Ƨ Slithering Loop Ƨ by ElChiglia (on 14. October 2023, 08:05) | 42 | 91 % |
| Doppler Effect (Roller Coaster) by Agent (on 3. January 2024, 09:00) | 40 | 98 % |
| A Mathematical Phenomenon by Xenonetix (on 4. September 2022, 22:22) | 92 | 100 % |
| Castle Woku (Castle Wall/Sudoku) by Wessel Strijkstra (on 16. December 2022, 16:49) | 37 | 99 % |
| Border Count Pentominous by Gliperal (on 13. March 2023, 00:08) | 33 | 96 % |
| Suguru Chaos Deconstruction #4: Renban + Japanese Sums by mathpesto (on 7. March 2022, 17:30) | 100 | 96 % |
| Schirmflechte Krypt by Luigi (on 25. August 2009, 11:14) | 30 | 90 % |
| F-Puzzle by PulverizingPancake (on 16. April 2021, 03:40) | 37 | 92 % |
| Disjointed Cube by antiknight (on 11. May 2022, 22:38) | 18 | 90 % |
| Mysterious Couple by sujoyku (on 19. November 2022, 13:20) | 17 | 96 % |
| Kill-o-meter by Jreg (on 12. January 2023, 07:35) | 13 | 92 % |
| Parity Loop #2: Irregular by Paletron (on 5. September 2023, 11:10) | 16 | 98 % |
| Wichtels (später) Rätselsommer 2024 (10): Yingu Jam by wichtel (on 3. October 2024, 20:23) | 15 | 92 % |
| Rätsel Siebenkampf by moss (on 29. September 2016, 22:00) | 38 | 99 % |
| Sliced Chaos Production by RockyRoer (on 27. November 2022, 12:37) | 44 | 98 % |
| pin7guin loves ABCtjes too by ibag (on 6. September 2017, 00:00) | 24 | 92 % |
| Whisper Doublers by yttrio (on 3. March 2023, 05:09) | 58 | 96 % |
| Armored Harriers by wooferzfg (on 30. April 2023, 06:06) | 26 | 100 % |
