(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 | |
|---|---|---|---|
 | Japanische Höhle mit Irrwisch von den Außerirdischen (2) by ibag (on 20. April 2018, 00:00) | 40 |  100 % |
| Daredevil (clone + thermo sudoku) by Aspartagcus (on 4. March 2021, 22:21) | 46 | 94 % |
| Japanese Sum Cave Cipher: Fillomino (Parity) by Niverio (on 18. November 2022, 18:32) | 41 | 100 % |
| Order! Order! by IcyFruit (on 17. November 2023, 13:57) | 44 | 98 % |
| Twin Rooms (Chaos Construction) by Agent (on 14. June 2022, 09:00) | 47 | 96 % |
| Mars Attacks! (2T1L CC) by Xenonetix (on 22. August 2022, 03:33) | 54 | 96 % |
| Offset Chaos by arbitrary (on 29. January 2025, 00:53) | 60 | 99 % |
| Disconnection by fritzdis (on 12. January 2023, 13:43) | 66 | 97 % |
| Chaos Construction: Circle Sum (9x9) by Jesper (on 15. January 2024, 15:10) | 100 | 100 % |
| Japanische Arithmetik II by tuace (on 25. June 2014, 17:30) | 38 | 99 % |
| Danke für die tolle Zeit! by ibag (on 10. February 2018, 16:00) | 34 | 99 % |
| Exploded Compass Sudoku by stephane.bura (on 7. January 2021, 20:00) | 38 | 100 % |
| 4-color killer sudoku #1 by Nylimb (on 18. February 2021, 04:42) | 23 | 98 % |
| Spotlight (Anti-King Arrow Sudoku) by EliasKar (on 5. May 2021, 18:18) | 28 | 99 % |
| Ones and Twos by FryTheGuy (on 9. November 2021, 02:27) | 34 | 96 % |
| Disjoint X Arrows by Mesmer (on 15. October 2021, 20:44) | 16 | 92 % |
| Renban-na-na-na-na-na by SirSchmoopy (on 18. March 2022, 02:30) | 25 | 100 % |
| Suguru Chaos Deconstruction: Solo Little Killers by crispy16 (on 10. April 2022, 21:17) | 79 | 99 % |
| Deconstructed Whiski by mathpesto (on 7. July 2022, 20:48) | 61 | 98 % |
| Quantum Whispers by tesseralis (on 17. July 2022, 01:09) | 22 | 100 % |
