(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 | |
|---|---|---|---|
 | Japanese Sums #3: Reef by Myxo (on 17. May 2023, 21:10) | 55 |  94 % |
| Numbered Corridors by RockyRoer (on 7. July 2022, 13:25) | 48 | 97 % |
| This + This = That by EricRathbun (on 1. November 2023, 15:55) | 46 | 97 % |
| Convergence by dawsonjones2020 (on 13. September 2024, 16:23) | 44 | 96 % |
| Höhlen-U-Bahn (Teil 3) by Zzzyxas (on 18. May 2019, 11:31) | 70 | 100 % |
| Lemures by PulverizingPancake (on 2. September 2021, 20:40) | 78 | 96 % |
| Whisper of the killer snake by Joseph nehme (on 27. August 2021, 18:07) | 34 | 95 % |
| Middle of the Road (Killer) by tallcat (on 13. February 2023, 08:00) | 73 | 97 % |
| Meander (Slitherlink/Japanese sums sudoku) by dumediat (on 11. August 2023, 12:25) | 31 | 96 % |
| Whimsical Whisper Snake by starwarigami (on 27. January 2024, 00:09) | 38 | 100 % |
| Numbered Rooms Sudoku by Qodec (on 24. January 2022, 19:19) | 117 | 97 % |
| Geburtstags-Mix Sudoku by Realshaggy (on 24. August 2020, 16:26) | 49 | 96 % |
| Build Your Own Killer: Master Designer 2 by Playmaker6174 (on 18. September 2023, 00:00) | 48 | 95 % |
| Anti King XL Thermo Killer by MavericksJD (on 24. October 2020, 20:05) | 28 | 96 % |
| Encaged 9 by Joseph nehme (on 3. January 2021, 12:20) | 66 | 99 % |
| Roller Coaster Fillomino #2 (9x9) by Jesper (on 21. April 2021, 09:08) | 57 | 100 % |
| Off with their heads! (Decapitated arrow sudoku) by Aspartagcus (on 8. September 2021, 08:38) | 18 | 98 % |
| Just do the Moth! by Nahileon (on 21. December 2021, 20:43) | 21 | 94 % |
| Tension by wooferzfg (on 19. June 2022, 08:27) | 23 | 94 % |
| Garden Fences by antiknight (on 24. June 2022, 01:44) | 25 | 93 % |
