(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 | |
|---|---|---|---|
 | Activated Japanese Sums by RockyRoer (on 12. November 2022, 13:36) | 21 |  95 % |
| 10-in-9 killer sudoku #3 by Nylimb (on 11. February 2020, 22:35) | 45 | 99 % |
| Loop Aquarium by wooferzfg (on 23. October 2022, 20:25) | 43 | 99 % |
| The Buddy System by Allagem (on 20. June 2024, 07:55) | 79 | 98 % |
| Die Kryptos - S04E05: U-Bahn unter Hochhäusern by tuace (on 21. January 2020, 08:06) | 46 | 100 % |
| Stepping Stones by RockyRoer (on 2. October 2021, 15:00) | 25 | 98 % |
| Patches and Stitches by Sktx (on 15. November 2021, 13:00) | 28 | 96 % |
| Split Decision by ViKingPrime (on 30. August 2023, 04:42) | 21 | 96 % |
| X Zip Line by antiknight (on 29. November 2023, 19:36) | 52 | 96 % |
| Total Chaos by Bert (on 5. June 2024, 18:32) | 23 | 98 % |
| grow so natural, i eat my kale by aqjhs (on 17. February 2025, 02:30) | 23 | 100 % |
| Wichtel 2016 (12 und Schluss): Unterirdische Katakomben mit Kerzenbeleuchtung by wichtel (on 12. October 2017, 21:01) | 26 | 98 % |
| Ta(x)i-Cab Sums: by RockyRoer (on 6. December 2020, 13:35) | 26 | 91 % |
| Killoc4tor: Kill List by starwarigami (on 14. November 2021, 03:07) | 24 | 100 % |
| Build Your Own Aquarium by wooferzfg (on 5. February 2022, 16:54) | 30 | 100 % |
| Repeater by mathpesto (on 19. March 2022, 04:47) | 51 | 99 % |
| Stroopwafel by pieguy (on 19. October 2023, 23:13) | 27 | 91 % |
| The Sun by EricRathbun (on 2. June 2024, 00:57) | 56 | 90 % |
| Red Lodge, Montana (Sudoku-Creek Hybrid) by mathpesto (on 24. December 2023, 17:10) | 113 | 97 % |
| kNights, uNite! by Alphish (on 17. July 2020, 02:33) | 33 | 91 % |
