(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 | |
|---|---|---|---|
 | Orbicular by egubachu (on 12. May 2024, 20:37) | 18 |  93 % |
| Fingertrap (disjoint) by SkepticalMario (on 28. August 2024, 00:00) | 20 | 95 % |
| Navigation by ThePedallingPianist (on 7. December 2024, 18:48) | 18 | 93 % |
| E : y² + xy = x³ + 12948x + 421776 by aqjhs (on 20. February 2025, 11:36) | 18 | 93 % |
| Trolley Problem by the_cogito (on 28. January 2025, 18:27) | 13 | 100 % |
| Dynamic Domino Sums by Jolly Rogers (on 22. May 2025, 18:53) | 41 | 94 % |
| 24HPC-Überbleibsel: Magnetschwebebahn by CJK (on 18. September 2025, 08:00) | 19 | 100 % |
| Don't Fret by ViKingPrime (on 8. October 2025, 04:00) | 17 | 93 % |
| Thermal Equilibrium (Chaos Construction) by Agent (on 19. July 2022, 09:00) | 107 | 99 % |
| The Moving Finger (Numbered Regions Chaos Construction) by tallcat (on 27. February 2025, 03:00) | 168 | 98 % |
| Breakthrough by Xenonetix (on 3. March 2023, 03:03) | 72 | 97 % |
| Chaos Construction: Region Sums by KNT (on 7. April 2022, 20:42) | 67 | 97 % |
| Chequered Arromino #2 by Phistomefel (on 25. May 2023, 20:32) | 109 | 99 % |
| Killer Sudoku(003) by cdwg2000 (on 4. September 2020, 01:04) | 54 | 97 % |
| Sudokutown is That Way by Aaronomys (on 20. February 2022, 14:26) | 42 | 99 % |
| Peristaltikmaschine (Chaos Construction) by glum_hippo (on 21. March 2025, 12:32) | 73 | 98 % |
| Just Wrogn Enough by lerroyy (on 20. May 2022, 18:23) | 69 | 96 % |
| Chaos Construction: Arachne by tesseralis (on 24. September 2022, 08:20) | 32 | 97 % |
| Coral Subway by wooferzfg (on 26. March 2023, 22:35) | 30 | 96 % |
| Slythering [Liar Japanese Sums Snake] by Christounet (on 4. June 2024, 07:54) | 31 | 100 % |
