(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 | |
|---|---|---|---|
 | Attention Deficit Disorder by HalfBakedLunatic (on 10. June 2023, 04:42) | 39 |  90 % |
| Cross-blunder by chameleon (on 29. June 2023, 23:24) | 11 | 95 % |
| Chaotic counting by palpot (on 16. December 2023, 00:08) | 78 | 98 % |
| Reban Arrow Sudoku by psninn (on 19. March 2024, 04:55) | 52 | 95 % |
| Parity Lines Sandwich by RockyRoer (on 29. April 2024, 03:41) | 17 | 92 % |
| Variety (6x6 Sudoku Pack) by Florian Wortmann (on 6. June 2024, 12:56) | 27 | 96 % |
| Thermal Counting Quads by MSDOS (on 28. June 2024, 02:51) | 24 | 92 % |
| The King's Round Table by DubiousMobius (on 29. September 2024, 03:12) | 31 | 92 % |
| Killer ratio by jcgodart (on 23. October 2024, 09:38) | 21 | 91 % |
| Polynesia (Nurikabe Deconstruction) by Agent (on 27. September 2022, 09:00) | 97 | 99 % |
| Eight Squares by jovi_al (on 26. September 2021, 23:34) | 111 | 97 % |
| Reachin' some region sums by twototenth (on 6. September 2022, 08:00) | 72 | 97 % |
| Whispering Mask by josh_johnson (on 4. June 2023, 16:34) | 47 | 92 % |
| ABC-Box mit Buchstabensalat-Kern mit Hochhaus-Kern by ibag (on 14. July 2013, 23:18) | 62 | 99 % |
| MasyU-Bahn (Teil 2) by Zzzyxas (on 2. April 2015, 20:35) | 60 | 99 % |
| KOPF - Buchstabenrätsel / Letter Puzzle by DocLogic (on 13. September 2020, 12:55) | 33 | 96 % |
| Positive Ring by SudokuExplorer (on 19. January 2021, 02:00) | 65 | 96 % |
| Cryptic Triptych (Thermo Kropki Sudoku) by EliasKar (on 20. February 2021, 18:57) | 38 | 91 % |
| Way out of my way by PrimeWeasel (on 1. September 2022, 20:36) | 34 | 92 % |
| Different Neighbours U-Bahn by Paletron (on 2. June 2024, 11:30) | 32 | 96 % |
