(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 | |
|---|---|---|---|
 | Quintessence [Pentominous Fillomino] by MicroStudy (on 29. June 2023, 21:28) | 80 |  95 % |
| Pseudoscience by marty_sears (on 7. February 2024, 19:54) | 226 | 96 % |
| Battlefield Sudoku #4: Knights! by Big Tiger (on 23. June 2020, 04:08) | 29 | 97 % |
| Sad Kropki by Zilou (on 12. September 2022, 01:08) | 34 | 90 % |
| Galactic Skirmish (Spiral Galaxy, Star Battle, Killer Sudoku) by AnalyticalNinja (on 1. February 2023, 02:21) | 97 | 95 % |
| Split Connections (U-Bahn + Loop) by Nordy (on 31. July 2023, 08:00) | 29 | 96 % |
| Sagittarius (Killer Sudoku ft. jovi_al) by purpl (on 7. October 2022, 01:39) | 80 | 94 % |
| Renban ModE - Little Killer/Renban sudoku by Mr.Menace (on 29. May 2021, 17:43) | 42 | 98 % |
| Suburbs by Nordy (on 11. November 2023, 11:11) | 41 | 93 % |
| Two Sums by CaptZebraCakes (on 26. January 2024, 20:57) | 42 | 96 % |
| Vertigo Yajilin #1 by Piatato (on 10. April 2024, 00:37) | 40 | 99 % |
| Negative X plus V by TheGreatGoatsbie (on 7. August 2024, 20:10) | 118 | 94 % |
| Ignition! (Thermo) by Blashyrkh (on 19. October 2024, 14:41) | 116 | 94 % |
| Endemic by NicoD (on 13. February 2026, 05:30) | 62 | 92 % |
| Sudoku Variants Series (351) - Double Trouble Killer Sudoku by Richard (on 15. December 2021, 00:00) | 78 | 96 % |
| Pac-Man Sudoku by mathpesto (on 10. June 2023, 04:50) | 131 | 95 % |
| Quali 2017 - Leftover: U-Bahn by ibag (on 29. January 2017, 20:17) | 53 | 98 % |
| LM 2018 Countdown: A 38 (1) by tuace (on 2. June 2018, 09:06) | 44 | 95 % |
| Parity Runs #3: Skyscraper by Madmahogany (on 10. June 2020, 20:17) | 45 | 94 % |
| Jeepers Creepers by panthchesh (on 21. May 2021, 05:00) | 24 | 90 % |
