(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 | |
|---|---|---|---|
 | Chaos: Killer by lerroyy (on 11. April 2022, 20:42) | 50 |  98 % |
| Questionable Chaos (Y-sums / Skyscrapers sums chaos construction) by Lizzy01 (on 30. May 2022, 11:59) | 20 | 95 % |
| Shadow by TotallyNormalCat (on 4. July 2022, 14:00) | 43 | 98 % |
| Three Kings Go Horse Riding by Scruffamudda (on 15. August 2022, 02:19) | 20 | 93 % |
| Killer Quads by RockyRoer (on 19. September 2022, 03:14) | 48 | 100 % |
| Anti-Arrow by Eclectic_Hoosier (on 12. October 2022, 06:28) | 16 | 93 % |
| Target Acquired (Equalines Sudoku) by Sktx (on 4. February 2023, 22:17) | 26 | 96 % |
| Cave Express (Japanese Sums Cipher) by Agent (on 21. February 2023, 09:00) | 56 | 99 % |
| Parasite by XeonRisq (on 10. March 2023, 17:00) | 27 | 93 % |
| Negative Space [Meta-Renban Sudoku] by wisty (on 12. April 2023, 10:41) | 23 | 93 % |
| Birefringence by Jay Dyer (on 25. August 2023, 20:46) | 64 | 96 % |
| Orbicular by egubachu (on 12. May 2024, 20:37) | 17 | 93 % |
| Typhon by Kafkapharnaum (on 24. August 2024, 19:41) | 34 | 98 % |
| Fingertrap (disjoint) by SkepticalMario (on 28. August 2024, 00:00) | 20 | 95 % |
| 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) | 40 | 94 % |
| pull prank by aqjhs (on 6. September 2025, 06:09) | 31 | 100 % |
| 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 % |
| The Ones Who Came Before by Manta-Ray (on 30. October 2025, 14:42) | 18 | 98 % |
