(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 Construction: Arachne by tesseralis (on 24. September 2022, 08:20) | 32 |  97 % |
| Coral Subway by wooferzfg (on 26. March 2023, 22:35) | 30 | 96 % |
| Parity Parity by vitaminz (on 3. July 2025, 15:18) | 99 | 95 % |
| Lunch box by Qodec (on 18. August 2020, 11:18) | 33 | 97 % |
| Mysterious Boxes by fjam (on 8. January 2023, 16:19) | 25 | 91 % |
| Pretending (with ChinStrap) by MSDOS (on 9. June 2025, 21:56) | 25 | 97 % |
| Killer Sudoku - Twirl by Phistomefel (on 6. December 2020, 11:18) | 76 | 98 % |
| 10-in-9 Killer Sudoku by KNT (on 10. May 2022, 01:14) | 48 | 97 % |
| 2T1L by ICHTUES (on 11. September 2022, 06:00) | 70 | 96 % |
| Wichtel 2015 (12 und Schluss): Hommage an eine Künstlerin by wichtel (on 18. July 2016, 21:50) | 34 | 96 % |
| Puffer Fish by Qodec (on 28. November 2020, 22:05) | 51 | 98 % |
| Sudokutown is That Way by Aaronomys (on 20. February 2022, 14:26) | 37 | 99 % |
| 3D2Y by udukos (on 9. November 2024, 20:45) | 39 | 97 % |
| Caudal Autotomy by DadJokes (on 19. August 2022, 21:11) | 28 | 97 % |
| Purple vs Green (Entropy Sudoku) by Mad-Tyas (on 4. April 2023, 10:14) | 39 | 93 % |
| RedivideR by goodcity (on 17. March 2024, 16:36) | 20 | 93 % |
| Toutatis by IcyFruit (on 9. May 2024, 14:35) | 44 | 93 % |
 | Split the Sums by palpot (on 4. January 2026, 10:00) | 20 | 97 % |
| Induction (Nonconsecutive German Whispers Sudoku) by Phistomefel (on 14. June 2022, 09:05) | 140 | 96 % |
| Summation U-Bahn by Agent (on 19. September 2023, 09:00) | 69 | 97 % |
