(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 | |
|---|---|---|---|
 | Box killer sudoku by udukos (on 20. August 2020, 11:06) | 70 |  97 % |
| Dude where's my XV? by PetLov (on 6. February 2021, 21:06) | 33 | 92 % |
| Don't be a smarTcaT ! by Christounet (on 19. June 2023, 17:48) | 31 | 98 % |
| Demiparure by mormagli (on 15. June 2024, 17:28) | 27 | 93 % |
| Ascending Starters Sudoku, 2025 by clover (on 1. January 2025, 10:47) | 29 | 93 % |
| Zwei Rundwege aufeinander by Micha (on 31. December 2010, 16:04) | 45 | 98 % |
| Yin Yang Multi-thermos by yttrio (on 8. March 2024, 20:20) | 73 | 98 % |
| Noch ein runder Rundweg 2 by Calavera (on 11. August 2009, 18:09) | 40 | 98 % |
| Palindromic Snake by Phistomefel (on 18. March 2020, 00:38) | 69 | 94 % |
| Spring Sudoku（1） by cdwg2000 (on 9. September 2020, 15:51) | 45 | 95 % |
| Sum-Product Snake by kolot (on 22. July 2021, 08:23) | 22 | 99 % |
| The 28th Party (CTC Secret Santa 2021) by Niverio (on 29. December 2021, 00:11) | 70 | 97 % |
| Faces by Pallando (on 11. March 2022, 11:53) | 20 | 100 % |
| Archer Towers by Angelo (on 12. May 2022, 20:09) | 19 | 94 % |
| Ocular by Maxentius (on 19. December 2022, 21:24) | 25 | 93 % |
| The Friendly Stars by Crusader175 (on 10. January 2023, 15:00) | 25 | 97 % |
| Strawberry Fields by cristophermoore (on 18. April 2023, 02:31) | 41 | 94 % |
| Stolen Whispers by Paquet Voleur (on 1. July 2023, 22:36) | 39 | 91 % |
| Modular Mirror by RockyRoer (on 3. October 2023, 11:52) | 69 | 94 % |
| Hardened Points by arbitrary (on 20. December 2023, 23:31) | 19 | 94 % |
