(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 | |
|---|---|---|---|
 | Doggo Adventure #11 by waffles_the_dog (on 9. February 2023, 10:56) | 33 |  91 % |
| Little Killer Around You by Ridhwan (on 19. November 2023, 03:40) | 27 | 94 % |
| Hakata (Shikaku Chaos Construction) by sfushidahardy (on 29. July 2024, 07:53) | 83 | 98 % |
| Sudoku Variants Series (332) - Teleportation Cycle Sums Sudoku by Richard (on 4. August 2021, 00:00) | 82 | 97 % |
| 真笑Puzzles040--Chaos Construction-- “孙子” 002 by cdwg2000 (on 19. May 2021, 14:59) | 27 | 99 % |
| Red Colour by apiyo (on 16. April 2022, 14:02) | 32 | 95 % |
| Why Did It Have To Be Snakes? by DadJokes (on 7. September 2022, 18:41) | 33 | 96 % |
| Warp Speed by The Bard (on 16. October 2024, 00:02) | 241 | 97 % |
| Electrostatic Discharge by Allagem (on 14. April 2024, 11:30) | 64 | 93 % |
| Pentomino-Hitori by tyskhubi (on 2. August 2014, 09:41) | 31 | 94 % |
| Hidden X-Sums & Sandwiches by BL00DW0LF (on 7. August 2020, 05:39) | 32 | 91 % |
| Killer X Sudoku by ICHTUES (on 9. May 2021, 06:00) | 60 | 95 % |
| Squeez Theorem (Suguru Deconstruction) by KevinTheMH (on 28. June 2023, 21:33) | 34 | 94 % |
| Arrows Accord by graggle (on 8. February 2025, 13:00) | 41 | 92 % |
| Fortune Cookie II by pieguy (on 20. November 2024, 01:23) | 154 | 96 % |
| Thermometer Sandwich Sudoku by Jesper (on 31. May 2020, 19:31) | 103 | 91 % |
| Mystery Box by Jolly Rogers (on 18. October 2023, 11:57) | 66 | 97 % |
| Floor Plan by the_cogito (on 15. March 2022, 20:39) | 38 | 95 % |
| Modulenburg by RockyRoer (on 14. June 2025, 13:13) | 90 | 95 % |
| Microclimate by NicoD (on 22. June 2025, 05:30) | 128 | 95 % |
