(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 | |
|---|---|---|---|
 | 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 % |
| Elephants & Castles by juggler (on 1. July 2024, 12:50) | 91 | 97 % |
| Burger Xtra by Wuschel (on 7. February 2026, 20:40) | 21 | 91 % |
| Umpteen by NicoD (on 26. February 2026, 05:30) | 53 | 92 % |
| Red Light, Green Light (Dynamic Fog) by Hanks (on 18. March 2026, 14:04) | 37 | 96 % |
| Japanische Krypto-Summen gratulieren by pin7guin (on 9. July 2016, 00:00) | 58 | 98 % |
| Pentopia Rundweg by tuace (on 22. April 2019, 09:55) | 65 | 99 % |
| JAMES BOND - Buchstabenrätsel by DocLogic (on 13. January 2020, 18:00) | 42 | 91 % |
| Six dots by Lutterot (on 18. May 2023, 22:46) | 40 | 92 % |
| Cháguăn by NicoD (on 25. May 2026, 05:30) | 45 | 92 % |
| Quiet Self-Reflection by Nordy (on 16. February 2025, 08:30) | 73 | 99 % |
| Valence by zetamath (on 12. August 2021, 19:08) | 62 | 97 % |
| T Time by EricRathbun (on 23. March 2022, 21:44) | 35 | 97 % |
| Stingray by mormagli (on 25. September 2022, 04:47) | 23 | 95 % |
| Synthesis (Killer/Renban/Antiknight) by dumediat (on 29. June 2023, 00:35) | 79 | 93 % |
| Shoot the Pears by tallcat (on 9. April 2021, 15:50) | 50 | 96 % |
| Spaces in Between (Windoku Between Kropki X) by tallcat (on 8. May 2022, 17:17) | 81 | 95 % |
| Holly (Killer Sudoku) by purpl (on 21. December 2025, 19:03) | 97 | 97 % |
| Loses Kalenderblatt April 2019 (1/2) by April (on 1. April 2019, 00:00) | 28 | 95 % |
