(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 | |
|---|---|---|---|
 | Cross Stitching 101 (Equalines Sudoku) by Sktx (on 1. November 2022, 15:51) | 32 |  90 % |
| Bashful Cages by Ennead (on 30. November 2022, 21:21) | 32 | 93 % |
| Whispers of Entropy 2: Balance by Mad-Tyas (on 6. March 2023, 09:01) | 32 | 98 % |
| Creepy Crawly (Killer Sudoku) by Phistomefel (on 28. February 2023, 07:35) | 107 | 97 % |
| Chaotic Indexers by mathpesto (on 15. July 2022, 22:15) | 30 | 100 % |
| COCKTAIL - Buchstabenrätsel / Letter Puzzle by DocLogic (on 26. August 2022, 13:55) | 30 | 93 % |
| Skyscraper Slingshot Sudoku #2 by Piatato (on 1. March 2023, 23:49) | 29 | 99 % |
| Euler Knights by Raumplaner (on 6. April 2023, 17:34) | 35 | 94 % |
| Orla The Octopus by ThePedallingPianist (on 9. February 2024, 19:41) | 32 | 99 % |
| Double Arrow Melt by Black_Doom (on 8. May 2024, 19:06) | 32 | 96 % |
| Zodiac-Killer VI : Virgo by Eisbär (on 8. September 2011, 23:56) | 61 | 96 % |
| Battle With The Archers 3: The Suspicious Butterfly by Playmaker6174 (on 14. June 2021, 13:06) | 62 | 98 % |
| Sudoku Variants Series (300) - Killer Skyscrapers Sudoku by Richard (on 22. December 2020, 22:00) | 95 | 97 % |
| Antiknight Cross by Raumplaner (on 18. December 2021, 16:08) | 34 | 94 % |
| Mexican Train by ViKingPrime (on 9. May 2023, 14:00) | 31 | 99 % |
| Webstuhl by GemmaOane (on 14. September 2023, 21:35) | 43 | 90 % |
| 2024 con un drum (Sudoku) by glum_hippo (on 5. January 2024, 17:19) | 32 | 93 % |
| Wreathe (Dual Masyu/Yin Yang) by dumediat (on 3. March 2024, 00:00) | 36 | 97 % |
| Konami Code by TotallyNormalCat (on 10. March 2021, 23:30) | 97 | 98 % |
| Rätselwochenende 2013: Rätselkreis by pwahs (on 13. March 2013, 18:30) | 59 | 99 % |
