(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 | |
|---|---|---|---|
 | Rundweg - Vertauschte Nachbarn by Calavera (on 28. June 2009, 13:47) | 71 |  94 % |
| Yin Yang Position Sums Sudoku by Jesper (on 3. November 2022, 19:17) | 74 | 97 % |
| Killer Sudoku (WSC 2019 Leftover) by Realshaggy (on 9. September 2019, 21:23) | 99 | 95 % |
| Rumors (German Whispers) by tallcat (on 8. October 2021, 17:02) | 158 | 98 % |
| Krypt-Rundweg verkehrt by lupo (on 8. July 2009, 14:35) | 25 | 96 % |
| ABC-Box mit Buchstabensalat-Kern mit Hochhaus-Kern by ibag (on 14. July 2013, 23:18) | 63 | 99 % |
| LM 2017 Reste: Hakyuu-Hitori by pwahs (on 6. April 2017, 10:00) | 39 | 94 % |
| LM Crossword by rimodech (on 26. April 2020, 21:16) | 20 | 95 % |
| Little Killer Twins by SudokuExplorer (on 26. September 2020, 02:00) | 41 | 96 % |
| FROHE WEIHNACHT - Buchstabenrätsel / Letter Puzzle by DocLogic (on 14. December 2020, 16:30) | 36 | 96 % |
| The Knot by tenaliraman (on 9. April 2021, 00:46) | 40 | 96 % |
| Living on the Diagonal by Sktx (on 25. May 2021, 00:10) | 11 | 98 % |
| Diamond by SirWoezel (on 21. June 2021, 11:20) | 10 | 90 % |
| Odd/Even Sandwich Sudoku by Piatato (on 2. August 2021, 13:33) | 46 | 91 % |
| Alphanumeric by jwsinclair (on 15. December 2021, 20:24) | 12 | 98 % |
| Snowflake by kuraban (on 31. December 2021, 00:38) | 26 | 98 % |
| The Palindrome Loop by FlowJo (on 5. January 2022, 11:27) | 18 | 95 % |
| Parity Arrows by Jay Dyer (on 22. January 2022, 11:54) | 17 | 93 % |
| X-Sums: 37 by the_cogito (on 1. February 2022, 16:58) | 10 | 98 % |
| The Clouds Give Way (Killer) by Aaronomys (on 6. March 2022, 18:35) | 43 | 97 % |
