(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 | |
|---|---|---|---|
 | Dumbbells by djorr (on 29. March 2022, 14:00) | 22 |  97 % |
| Pieces of the Puzzle by grkles (on 22. February 2022, 01:39) | 20 | 99 % |
| Prison Negativity by Prof.Dori (on 30. January 2024, 18:54) | 19 | 91 % |
| Not Just Once by jwsinclair (on 11. January 2024, 21:14) | 97 | 97 % |
| Whispers in the Night by ___ (on 13. June 2021, 05:24) | 48 | 95 % |
| Cryptic Star Nurikabe by BenceJoful (on 24. September 2021, 09:19) | 44 | 100 % |
| Branches (arrow sudoku) by Aspartagcus (on 12. September 2023, 13:44) | 67 | 94 % |
| Lockset by Xenonetix (on 25. June 2023, 21:12) | 51 | 91 % |
| Central Difference Method by JMoat13 (on 25. August 2023, 23:06) | 52 | 92 % |
| Little Killer Around You by Ridhwan (on 19. November 2023, 03:40) | 25 | 97 % |
| Siamese Rundweg Sudoku Twins by pokerke (on 2. December 2010, 21:35) | 47 | 96 % |
| LM-Training: Five Fences by JonaS2010 (on 31. May 2018, 22:15) | 52 | 98 % |
| Rooks are Better by meggen033 (on 23. September 2022, 09:43) | 33 | 94 % |
| Doggo Adventure #11 by waffles_the_dog (on 9. February 2023, 10:56) | 29 | 91 % |
| Ringban Octopus by ThePedallingPianist (on 22. August 2024, 14:23) | 25 | 93 % |
| [New Constraint] Entropy Sudoku by Mad-Tyas (on 3. December 2021, 05:28) | 115 | 92 % |
| LM 2023 Überbleibsel - Japanische Summen, schwierigere Version by Zzzyxas (on 8. July 2023, 20:23) | 54 | 97 % |
| Wingnuts by FullDeck-Missing (on 7. September 2024, 13:09) | 57 | 91 % |
| High Life by Aaronomys (on 24. April 2021, 10:29) | 32 | 98 % |
| Connon by PrimeWeasel (on 4. July 2021, 11:06) | 27 | 92 % |
