(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 | |
|---|---|---|---|
 | Arrows to the gates of hell by damasosos92 (on 6. February 2024, 23:17) | 13 |  96 % |
| Regionometers by ThePedallingPianist (on 20. February 2024, 13:20) | 30 | 96 % |
| Thirteen Ghosts by mathpesto (on 19. September 2024, 22:37) | 64 | 100 % |
| U-Bahn with Fillomino enclosures #3 (12x12) by Jesper (on 10. November 2024, 13:37) | 30 | 99 % |
| [TSL][S1T6] Across the Stars by The Book Wyrm (on 30. July 2025, 17:07) | 16 | 98 % |
| Entropy Antimatter by Mad-Tyas (on 5. March 2024, 16:24) | 38 | 93 % |
| The Moving Finger (Numbered Regions Chaos Construction) by tallcat (on 27. February 2025, 03:00) | 148 | 98 % |
| Indexed Chaos by Jay Dyer (on 3. September 2022, 23:42) | 79 | 100 % |
| Killer Sudoku(003) by cdwg2000 (on 4. September 2020, 01:04) | 52 | 98 % |
| Gabe Ruth hits a homerun by SirWoezel (on 28. April 2021, 18:49) | 28 | 96 % |
| Cycle (Between lines sudoku) by Lizzy01 (on 8. September 2021, 10:45) | 21 | 97 % |
| Wordless Kakuro by qiuyanzhe (on 26. November 2021, 08:34) | 21 | 92 % |
| 10-in-9 Killer Sudoku by KNT (on 10. May 2022, 01:14) | 44 | 97 % |
| Schrodinger's Split Peas by SamuPiano (on 12. July 2024, 15:44) | 42 | 97 % |
| Japanese Slitherlink by KNT (on 27. October 2024, 22:43) | 45 | 100 % |
| Double negative by filuta (on 26. January 2025, 12:28) | 21 | 100 % |
| BYO Kropki Cages by mathpesto (on 10. December 2022, 02:33) | 74 | 99 % |
| Repeat Prescription by Jay Dyer (on 21. July 2024, 00:11) | 52 | 97 % |
| Chaos Construction: Killer Cages by KNT (on 4. April 2022, 23:31) | 125 | 96 % |
| Chequered Arromino #2 by Phistomefel (on 25. May 2023, 20:32) | 106 | 99 % |
