(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 | |
|---|---|---|---|
 | Doppel-Killer Sudoku 0/1-9 by julius64 (on 27. January 2011, 22:21) | 46 |  94 % |
| Fish food by Qodec (on 4. December 2020, 23:21) | 52 | 97 % |
| Odd/Even Consecutive Killer 4 by Quarterthru (on 9. January 2021, 12:00) | 24 | 95 % |
| 真笑Puzzles030--69Sandwich(4) - -Uncertain Double Sandwich by cdwg2000 (on 25. February 2021, 12:30) | 22 | 100 % |
| Súmmetros by Lisztes (on 1. October 2021, 01:00) | 46 | 97 % |
| Sum-Product Snake by kolot (on 22. July 2021, 08:23) | 23 | 99 % |
| Broken Cello by Tyrgannus (on 9. October 2021, 21:02) | 52 | 93 % |
| World of Weird Wonders - A 7x7 Irregular Sudoku Pack by Playmaker6174 (on 18. December 2021, 10:35) | 22 | 93 % |
| Piatato's challenge by filuta (on 2. July 2022, 18:01) | 27 | 95 % |
| The Grand Design (Numbered Room combo) by Playmaker6174 (on 27. July 2022, 05:54) | 22 | 95 % |
| Ocular by Maxentius (on 19. December 2022, 21:24) | 28 | 91 % |
| X-Secret by Prof.Dori (on 20. June 2023, 23:50) | 25 | 92 % |
| Japanische Summen mit Hochhaushinweisen by Zzzyxas (on 6. September 2024, 00:00) | 41 | 99 % |
| Limited Occupancy by Jay Dyer (on 11. February 2025, 23:32) | 144 | 96 % |
| The lost oriel by NicoD (on 30. May 2025, 05:30) | 30 | 92 % |
| Terra Incognita (with ChinStrap) by sujoyku (on 4. July 2025, 16:11) | 49 | 95 % |
| Zhōngguó Ěryǔ by Prof.Dori (on 9. September 2025, 19:30) | 21 | 92 % |
| The Pairrow's Surveyors by Andrewsarchus (on 14. January 2026, 06:30) | 22 | 98 % |
| have you had enough? by aqjhs (on 28. December 2025, 01:23) | 59 | 96 % |
| Tower of Babel by Jay Dyer (on 6. June 2023, 17:47) | 154 | 96 % |
