(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 | |
|---|---|---|---|
 | Little Irregular Killer 2 by Richard (on 29. August 2012, 12:00) | 76 |  94 % |
| Diagonal-Windoku by ibag (on 29. December 2011, 20:09) | 65 | 95 % |
| Binary Sudoku 11 by stephane.bura (on 26. April 2020, 23:39) | 19 | 96 % |
| Ramparts by SSG (on 11. October 2021, 12:15) | 17 | 90 % |
| Seventh Night by SSG (on 1. December 2021, 07:07) | 66 | 93 % |
| Phone in your Crossword Puzzle By Olima and PanthChesh by panthchesh (on 8. March 2022, 04:09) | 16 | 90 % |
| Aqraf by CJK (on 24. October 2022, 19:49) | 37 | 94 % |
| Production Lines by Mr Toffee (on 5. June 2024, 17:35) | 19 | 93 % |
| Octoquadri Pack (volume 4) by The Book Wyrm (on 3. January 2025, 16:58) | 19 | 96 % |
| Irregular Killer Sudoku 4 by Azure (on 14. April 2025, 15:18) | 39 | 91 % |
| Anti-Kropki Cages by marty_sears (on 7. August 2025, 07:31) | 186 | 96 % |
| Parity Party II - "Little Killer at Summer Camp" by glum_hippo (on 11. April 2020, 20:54) | 52 | 91 % |
| Cryptic Star Nurikabe by BenceJoful (on 24. September 2021, 09:19) | 49 | 100 % |
| Ninth Court by Tyrgannus (on 28. October 2021, 13:36) | 51 | 96 % |
| Doppelganger: Crypto Japanese Cave by KNT (on 1. April 2023, 04:05) | 48 | 100 % |
| Lockset by Xenonetix (on 25. June 2023, 21:12) | 56 | 91 % |
| Pünktchen Sudoku 4 by Richard (on 6. June 2009, 23:46) | 145 | 90 % |
| Juni Domino Monat (2) - Hochhausdomino by Richard (on 8. June 2012, 12:00) | 51 | 96 % |
| LM-Training: Five Fences by JonaS2010 (on 31. May 2018, 22:15) | 53 | 98 % |
| Oil, Water, Whisper by Blobz (on 22. July 2024, 16:00) | 136 | 96 % |
