(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 | |
|---|---|---|---|
 | Rubber Bullets (10x10 Chaos Construction) by the_cogito (on 27. September 2022, 15:39) | 37 |  99 % |
| Thermohaline (Nurikabe Thermo Sudoku) by Agent (on 11. October 2022, 09:00) | 37 | 98 % |
| Vivi Loca (Irregular Killer Sudoku) by Qodec (on 2. May 2023, 15:30) | 39 | 94 % |
| Chaos Construction: XY-Sums by ns08 (on 28. May 2023, 23:55) | 28 | 93 % |
| Highway to the Danger Zone by Jay Dyer (on 23. May 2023, 21:52) | 57 | 93 % |
| The Ankheg (Zippular Lines #4) by heliopolix (on 30. December 2023, 16:36) | 14 | 95 % |
| Megascops Asio by Sniglett (on 21. February 2025, 01:39) | 11 | 100 % |
| Pfeilchenbeet / Arrow Farm by Phistomefel (on 17. November 2020, 20:01) | 49 | 99 % |
| Order Out Of Chaos by zzw (on 16. November 2023, 00:45) | 35 | 100 % |
| So Very Wrogn by tallcat (on 20. June 2023, 08:00) | 60 | 91 % |
| The Barrel (Arrow Sudoku) by tallcat (on 18. April 2021, 05:29) | 87 | 100 % |
| Zweiter Pfeilchenstrauß by glum_hippo (on 24. August 2020, 17:26) | 24 | 93 % |
| Compass Fillomino #3: Large grid by MagnusJosefsson (on 23. April 2021, 17:44) | 44 | 100 % |
| Fairy Rings by Jay Dyer (on 1. January 2022, 20:17) | 44 | 98 % |
| Thermo Battle by 10feet (on 18. February 2022, 17:00) | 20 | 97 % |
| The Map by PotatoHead21 (on 21. December 2022, 07:19) | 24 | 96 % |
| Snakomino Warp Zones [Level #3] by Christounet (on 11. April 2023, 22:22) | 24 | 99 % |
| Crusties ("Indexed Fives") by RockyRoer (on 21. July 2023, 20:01) | 42 | 96 % |
| Summation U-Bahn #5: Sorted Clues by Agent (on 22. October 2024, 09:00) | 19 | 100 % |
| Crypto Japanese Slitherlink by KNT (on 12. November 2022, 22:43) | 50 | 100 % |
