(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 | |
|---|---|---|---|
 | A Deal With the Devil by ViKingPrime (on 14. December 2023, 16:30) | 25 |  98 % |
| Porcelain by egubachu (on 5. August 2024, 10:32) | 68 | 94 % |
| Anti-Fortress Arrow Sudoku by Phistomefel (on 17. January 2021, 21:52) | 87 | 94 % |
| Sequential Killer Sudoku by SenatorGronk (on 3. August 2020, 15:22) | 54 | 99 % |
| Disoriented (Chaos Construction) by Agent (on 3. January 2023, 09:00) | 50 | 99 % |
| The Great River by Blobz (on 23. December 2024, 16:00) | 93 | 94 % |
| Aquarium Sudoku by Sam Knott (on 20. June 2020, 13:07) | 26 | 93 % |
| Odd Trios Killer Sudoku by Quarterthru (on 19. September 2020, 12:00) | 26 | 99 % |
| Battle With The Archers 22: Double Speculations by Playmaker6174 (on 26. November 2021, 10:06) | 22 | 92 % |
| Hopscotch (Remix) by Nordy (on 3. September 2022, 08:00) | 44 | 95 % |
| Mayfair (Anti-King Region Sum Lines) by Xendari (on 8. November 2022, 08:22) | 25 | 97 % |
| Madrigal by Fafrd (on 1. January 2023, 17:41) | 108 | 93 % |
| Peaucellier-Lipkin by Palfly Kampling (on 22. July 2023, 05:20) | 26 | 97 % |
| Sightseeing (Aquapelago Chaos Deconstruction, 9x9) by thoughtbyte (on 11. September 2023, 10:49) | 25 | 93 % |
| Peel Back the Layers by XeonRisq (on 10. December 2023, 04:00) | 23 | 93 % |
| Writing a Zeugma by 99%Sneaky (on 7. July 2024, 22:21) | 26 | 95 % |
| XV Kropki Sudoku by Phistomefel (on 26. September 2020, 15:33) | 121 | 91 % |
| 1001-Nacht-Rundwege aus Paralleluniversen by ibag (on 4. November 2013, 05:55) | 34 | 99 % |
| Snake in the City by Lizzy01 (on 28. November 2021, 14:24) | 40 | 95 % |
| Hidden X-Sums by RockyRoer (on 8. August 2022, 17:48) | 37 | 99 % |
