(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 | |
|---|---|---|---|
 | Double Negative by Scruffamudda (on 9. June 2022, 00:32) | 60 |  94 % |
| Wichtel 2015 (3): Maschinelle Synthese by wichtel (on 24. March 2016, 10:25) | 48 | 98 % |
| Stepping Stones by grkles (on 10. July 2024, 18:05) | 99 | 98 % |
| Zeltplatz im Zauberwald by SilBer (on 21. November 2010, 20:33) | 50 | 96 % |
| Killer Sanduhr by tuace (on 3. November 2013, 04:30) | 46 | 97 % |
| 10-in-9 sandwich sudoku by Nylimb (on 26. March 2020, 10:16) | 50 | 98 % |
| Compass Sudoku by stephane.bura (on 5. November 2020, 20:00) | 52 | 99 % |
| Trebuchet (Slingshot Multi-Sudoku) by tallcat (on 5. July 2023, 08:00) | 49 | 96 % |
| Auteur by SamuPiano (on 14. August 2024, 15:44) | 51 | 98 % |
| Handshake (Arrow Sudoku) by Niverio (on 15. July 2022, 01:08) | 99 | 98 % |
| Heat Flow by Mad-Tyas (on 8. November 2022, 09:18) | 55 | 95 % |
| Corners and Sum Lines by Jolly Rogers (on 7. March 2024, 22:17) | 52 | 96 % |
| Hidden Pentominoes Killer/Little Killer Sudoku by MagnusJosefsson (on 6. May 2021, 13:07) | 46 | 98 % |
| Back & Forth by fjam (on 29. September 2022, 13:52) | 43 | 93 % |
| Xtravaganza (S-Cell XV Sudoku X) by tallcat (on 26. October 2022, 09:00) | 46 | 98 % |
| Inner Peas by SamuPiano (on 17. July 2024, 15:44) | 53 | 98 % |
| Cave Panem (Anti-XV Sandwich) by Phistomefel (on 27. February 2022, 07:22) | 147 | 97 % |
| Ten Arrows (Classic Arrow Sudoku) by EliasKar (on 5. February 2021, 01:35) | 48 | 97 % |
| Renban Skyscrapers by Florian Wortmann (on 26. June 2021, 13:41) | 41 | 93 % |
| Xaos by grkles (on 2. December 2022, 13:41) | 92 | 98 % |
