(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 | |
|---|---|---|---|
 | The Hare and the Tortoise by ThePedallingPianist (on 12. September 2024, 04:52) | 108 |  96 % |
| Addierter Neuner in Doppelpack by Richard (on 5. February 2010, 12:00) | 69 | 93 % |
| Mehrdeutige Rätsel - U-Bahn 3 by Zzzyxas (on 6. September 2017, 00:49) | 38 | 96 % |
| Castle Wall by Mark Sweep (on 22. January 2021, 10:00) | 22 | 92 % |
| Cascade by twototenth (on 20. July 2021, 08:00) | 21 | 93 % |
| Kropki Sums by mathpesto (on 19. December 2021, 16:26) | 22 | 94 % |
| Saturn's Moons by cristophermoore (on 9. June 2022, 00:25) | 66 | 100 % |
| Double Equals by josh_johnson (on 13. August 2022, 23:59) | 21 | 96 % |
| Three in the spotlight by Fool on Hill (on 11. September 2022, 15:21) | 24 | 93 % |
| Chaos Construction - Border Gaps by Mark Sweep (on 4. January 2023, 10:00) | 23 | 99 % |
| Chaos Deconstruction: Japanese Sum Cross the Streams Cipher by abed hawila (on 30. March 2023, 17:02) | 45 | 97 % |
| Run For Cover by 99%Sneaky (on 6. June 2023, 23:47) | 25 | 90 % |
| Friendly Borders by Prof.Dori (on 15. August 2024, 23:58) | 43 | 91 % |
| Hellseherische X-Sums (Sudoku) by glum_hippo (on 13. February 2025, 04:58) | 23 | 94 % |
| Double Dip by zetamath (on 21. June 2022, 19:38) | 72 | 97 % |
| Circle of Stars (Renban Quadruples) by Tyrgannus (on 4. April 2023, 21:33) | 49 | 92 % |
| HalfYin-TwoYang by DJV (on 11. January 2023, 15:37) | 75 | 94 % |
| Hiding Spots by Xendari (on 27. May 2023, 10:21) | 76 | 96 % |
| Battle With The Archers 6: Fallen Archer's Vow by Playmaker6174 (on 5. July 2021, 08:56) | 43 | 97 % |
| Chaos Construction: 2nd Region X-Sums #2 (9x9) by Jesper (on 5. April 2022, 11:15) | 63 | 100 % |
