(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 | |
|---|---|---|---|
 | Chaos Zippers by Visumation (on 19. January 2025, 13:10) | 63 |  94 % |
| Anti-Knight Uprising by Scruffamudda (on 4. April 2024, 05:42) | 65 | 94 % |
| Numbered Walls by Niverio (on 21. July 2022, 23:57) | 65 | 100 % |
| Magnet+Antimagnet-Verrückte Welt der Pole by r45 (on 11. August 2010, 16:28) | 68 | 92 % |
| Renban -Kakuro 1-10 / 2 by julius64 (on 4. May 2011, 21:18) | 65 | 94 % |
| Benebelte Nachbarschaft (FOW) by Myxo (on 19. August 2023, 05:25) | 338 | 96 % |
| Scattered X-Sums Sudoku (2) by Richard (on 13. June 2014, 12:00) | 74 | 94 % |
| Suguru Chaos Deconstruction by mathpesto (on 12. February 2022, 23:45) | 171 | 99 % |
| Fully Booked [Numbered Rooms Fillomino] by MicroStudy (on 26. January 2024, 12:26) | 100 | 97 % |
| Transmission by Phistomefel (on 18. January 2023, 17:39) | 263 | 97 % |
| Twin Killer Sudoku 2008-2009 by Richard (on 1. January 2009, 00:01) | 161 | 93 % |
| Rundweg auf der Kleinschen Flasche by flooser (on 14. November 2009, 12:52) | 54 | 91 % |
| Mannlzeug: Neinerlaa by Pyrrhon (on 24. December 2009, 18:00) | 42 | 91 % |
| RiesenRenbanKropki by Richard (on 26. March 2010, 12:00) | 70 | 90 % |
| Teamwettbewerb 2011: Rätselstern (Runde 1) by SilBer (on 30. March 2011, 20:52) | 62 | 97 % |
| Treppen (4) by BFaw (on 28. August 2012, 09:00) | 25 | 94 % |
| Adventsportale, Teil 2 by pirx (on 9. December 2018, 12:00) | 34 | 97 % |
| U-Bahn mit gemischten Hinweisen (Teil 1) by Zzzyxas (on 28. December 2019, 13:32) | 48 | 99 % |
| "Incomplete" Killer Sudoku by Greg (on 12. June 2020, 01:55) | 24 | 90 % |
| Yajilin Sudoku by Madmahogany (on 19. July 2020, 12:39) | 35 | 94 % |
