(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 | |
|---|---|---|---|
 | Parity Party XXVIII, "Party Mirror" by glum_hippo (on 30. March 2023, 13:57) | 34 |  94 % |
| Cross Whispers by Fool on Hill (on 1. June 2023, 15:08) | 58 | 93 % |
| Sightseeing (Aquapelago Chaos Deconstruction, 9x9) by thoughtbyte (on 11. September 2023, 10:49) | 24 | 93 % |
| Meidjuizy by Lizzy01 (on 14. November 2023, 11:36) | 33 | 100 % |
| Happy Birthday to Naomi by Fool on Hill (on 31. March 2024, 13:51) | 21 | 96 % |
| Philly by zetamath (on 8. July 2024, 01:14) | 34 | 94 % |
| Interlude (6 x 6 Puzzle Pack) by tallcat (on 25. July 2024, 08:00) | 19 | 93 % |
| Black and White by zetamath (on 12. February 2021, 23:34) | 78 | 98 % |
| Sudoku Variants Series (303) - Assorted Sandwiches Sudoku by Richard (on 13. January 2021, 00:00) | 73 | 98 % |
| Burrows by jovi_al (on 18. July 2021, 03:38) | 70 | 96 % |
| Reversi by Wuschel (on 5. November 2023, 21:18) | 72 | 96 % |
| Ringban by Ridhwan (on 1. March 2023, 07:21) | 63 | 91 % |
| Anti-King Thermo Sudoku by Blashyrkh (on 26. January 2024, 16:35) | 62 | 95 % |
| Siamese Rundweg Sudoku Twins 6x6 by pokerke (on 11. December 2010, 21:40) | 48 | 99 % |
| Sudoku Variants Series (245) - Counting Neighbours Sudoku by Richard (on 4. December 2018, 00:00) | 99 | 92 % |
| Diamonds And Butterflies by Niverio (on 15. July 2023, 17:58) | 52 | 94 % |
| Imprisoned (Killer Rooms Sudoku) by Agent (on 2. July 2022, 09:00) | 84 | 99 % |
| "Nevermore" ... than Four by XeonRisq (on 13. June 2021, 17:00) | 63 | 94 % |
| Center of Attention (Qodec's Tribute Puzzle) by Playmaker6174 (on 4. November 2022, 09:42) | 67 | 97 % |
| Killeriana: Ein anderer Psycho-Killer by Pyrrhon (on 2. September 2009, 17:39) | 81 | 93 % |
