(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 | |
|---|---|---|---|
 | Foursquare by NicoD (on 6. May 2025, 05:30) | 52 |  95 % |
| Skystaplers by ChinStrap (on 1. July 2025, 15:59) | 54 | 98 % |
| Brasero by NicoD (on 23. September 2025, 05:30) | 30 | 92 % |
| Jigsaw by Kaktuslav (on 11. October 2025, 08:00) | 44 | 94 % |
| Tail of the Okapi by glum_hippo (on 22. December 2025, 20:41) | 12 | 98 % |
| Recess by oskode (on 9. January 2026, 10:05) | 40 | 91 % |
| Wormholes (Chaos Construction) by kingoffries (on 28. May 2025, 18:27) | 129 | 97 % |
| Dustpan (Disjoint parity sweeper sudoku) by Qodec (on 23. February 2023, 13:00) | 124 | 97 % |
| Undeca Error (Killer, Anti-Knight) by Chilly (on 5. September 2022, 19:28) | 95 | 96 % |
| Alarm by zetamath (on 14. November 2023, 01:29) | 98 | 91 % |
| Binary star by NicoD (on 9. April 2025, 05:47) | 94 | 97 % |
| Box killer sudoku by udukos (on 20. August 2020, 11:06) | 71 | 97 % |
| Frak Redux (Ten Lines) by tallcat (on 25. October 2023, 09:00) | 61 | 95 % |
| Parroty Lines by marty_sears (on 29. April 2024, 13:52) | 177 | 95 % |
| Zwei Rundwege aufeinander by Micha (on 31. December 2010, 16:04) | 46 | 98 % |
| Memphis by ICHTUES (on 20. February 2022, 06:00) | 52 | 95 % |
| Full House by juggler (on 20. June 2024, 01:17) | 104 | 97 % |
| The Quaker's Quiver by mathpesto (on 13. January 2025, 05:20) | 49 | 92 % |
| Cave Sudoku by Phistomefel (on 10. July 2020, 12:39) | 98 | 96 % |
| Noch ein runder Rundweg 2 by Calavera (on 11. August 2009, 18:09) | 41 | 98 % |
