(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 | |
|---|---|---|---|
 | Whispers In The Shadows by Scruffamudda (on 15. January 2026, 08:23) | 80 |  94 % |
| Tag 13 - Nurikabe by CJK (on 28. January 2021, 16:18) | 50 | 92 % |
| Contiguous by grkles (on 21. May 2022, 13:07) | 57 | 92 % |
| Sum Amount of Trouble by Tyrgannus (on 20. August 2023, 00:08) | 96 | 95 % |
| Anti-killer Sudoku by JoJoMcFroYo (on 26. June 2020, 14:55) | 25 | 90 % |
| X-Parity by LKegel (on 19. February 2021, 17:31) | 22 | 96 % |
| Lil' Kill by PrimeWeasel (on 11. March 2021, 07:29) | 38 | 90 % |
| Little Killer Thermo Palindrome Sudoku by Cane_Puzzles (on 19. March 2021, 16:16) | 48 | 94 % |
| Sandwich-Sudoku mit Average Arrows by glum_hippo (on 18. April 2021, 06:00) | 66 | 100 % |
| Hybridsudoku: Winterurlaub in Südtirol by glum_hippo (on 5. December 2021, 19:52) | 21 | 94 % |
| Ring Of Entropy by crispy16 (on 7. September 2022, 15:56) | 29 | 99 % |
| Whose Line is it Anyway? (Region Sum, Renban, Global Entropy) by Chefofdeath (on 16. June 2024, 18:21) | 39 | 93 % |
| Bouquet of Poppies by Sotehr (on 17. January 2025, 10:00) | 47 | 90 % |
| Double Stacks by bboom (on 24. May 2025, 14:46) | 29 | 92 % |
| Spaces in Between (Windoku Between Kropki X) by tallcat (on 8. May 2022, 17:17) | 80 | 95 % |
| Pentopia Rundweg by tuace (on 22. April 2019, 09:55) | 65 | 99 % |
| LM 2018 Countdown: Japanisches Summen-Masyu by Uhu (on 7. June 2018, 09:06) | 47 | 96 % |
| Six dots by Lutterot (on 18. May 2023, 22:46) | 40 | 92 % |
| Quiet Self-Reflection by Nordy (on 16. February 2025, 08:30) | 73 | 99 % |
| Doppelter Rundweg by SilBer (on 4. July 2009, 11:21) | 83 | 95 % |
