(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 | |
|---|---|---|---|
 | Heat Flow by Mad-Tyas (on 8. November 2022, 09:18) | 55 |  95 % |
| Liar Japanese Sums #4 - Ciphered Yin Yang by Niverio (on 1. February 2023, 11:22) | 46 | 99 % |
| Auteur by SamuPiano (on 14. August 2024, 15:44) | 50 | 98 % |
| Stepping Stones by grkles (on 10. July 2024, 18:05) | 94 | 98 % |
| Hidden Pentominoes Killer/Little Killer Sudoku by MagnusJosefsson (on 6. May 2021, 13:07) | 46 | 98 % |
| Back & Forth by fjam (on 29. September 2022, 13:52) | 43 | 93 % |
| Trebuchet (Slingshot Multi-Sudoku) by tallcat (on 5. July 2023, 08:00) | 47 | 96 % |
| Corners and Sum Lines by Jolly Rogers (on 7. March 2024, 22:17) | 51 | 96 % |
| Renban X-sums sudoku by udukos (on 20. July 2021, 19:45) | 39 | 100 % |
| Numbered Rooms Sudoku 2 by Lizzy01 (on 4. January 2022, 22:03) | 49 | 90 % |
| Hieroglyph (Entropic Killer) by tallcat (on 15. October 2022, 18:02) | 48 | 94 % |
| 58 by Qodec (on 10. October 2020, 16:34) | 44 | 97 % |
| Geometry Exam #3 by Blashyrkh (on 7. August 2023, 19:46) | 49 | 94 % |
| Copycat Collaboration by Scojo (on 28. June 2024, 13:38) | 52 | 100 % |
| Rätselwochenende: Table for Four - Battleship by uvo (on 26. November 2014, 16:40) | 39 | 94 % |
| LM-Training: Japanisches Summen-Masyu by rob (on 4. June 2018, 23:22) | 43 | 93 % |
| Entroban by jcgodart (on 11. December 2022, 04:56) | 44 | 96 % |
| Angels by goodcity (on 8. October 2023, 18:03) | 45 | 93 % |
| Thorny issues [German Whisper Deconstruction] by Christounet (on 17. February 2023, 23:36) | 86 | 98 % |
| Double-Digit-Thermo I "The Tree" by Garford (on 23. January 2021, 19:04) | 52 | 96 % |
