(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 | |
|---|---|---|---|
 | Changeling Confusion by Scojo (on 31. October 2025, 23:31) | 15 |  94 % |
| Chaos Construction: Position Sums (9x9) by Jesper (on 12. October 2021, 20:35) | 81 | 100 % |
| Vignettes by zetamath (on 18. July 2022, 00:54) | 84 | 99 % |
| Perfectly Balanced by IcyFruit (on 13. February 2025, 14:33) | 87 | 97 % |
| Tír na nÓg by Qodec (on 17. July 2022, 10:20) | 67 | 98 % |
| Everything Is Rihgt by DiMono (on 30. September 2022, 03:03) | 94 | 95 % |
| Whispering Knight by Phistomefel (on 22. October 2021, 01:13) | 145 | 94 % |
| Clock Faces Sudoku by Phistomefel (on 21. August 2020, 16:50) | 41 | 93 % |
| Castle Wall/Cave #2 by MagnusJosefsson (on 28. May 2021, 10:02) | 35 | 98 % |
| Advanced Kinematics (Projected Sum Arrow) by tallcat (on 6. April 2022, 20:08) | 38 | 90 % |
| Perforate by Xendari (on 14. July 2022, 08:22) | 38 | 98 % |
| Counting Circles in Circles by egubachu (on 16. April 2025, 04:43) | 39 | 94 % |
| Quem Dixere Chaos by mathpesto (on 9. February 2022, 05:06) | 59 | 96 % |
| Entropical Pairadise (Pairrow, Yin Yang) by DubiousMobius (on 23. January 2025, 16:44) | 63 | 99 % |
| Beyond (Nurikabe Sudoku) by MaizeGator (on 15. July 2025, 20:10) | 86 | 97 % |
| Squares and Circles by Burning Curtains (on 15. August 2021, 20:17) | 43 | 98 % |
| Despair by XeonRisq (on 3. March 2024, 21:00) | 21 | 97 % |
| Schadenfreude by Andrewsarchus (on 11. September 2025, 23:51) | 27 | 100 % |
| 4 Line Theorem by Manta-Ray (on 19. December 2025, 22:56) | 70 | 97 % |
| Heyawake Sudoku by SennyK (on 22. January 2026, 22:02) | 28 | 96 % |
