(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 | |
|---|---|---|---|
 | yo tenía diez perritos by aqjhs (on 28. July 2025, 05:53) | 18 |  98 % |
| Pretending (with ChinStrap) by MSDOS (on 9. June 2025, 21:56) | 35 | 98 % |
| Boxwood Lane by 5Head (on 27. April 2026, 08:04) | 21 | 92 % |
| 4-color killer sudoku #2 by Nylimb (on 3. April 2021, 04:45) | 119 | 98 % |
| The Buddy System by Allagem (on 20. June 2024, 07:55) | 82 | 98 % |
| Short Arrows by Las4one (on 17. December 2024, 11:16) | 43 | 95 % |
| I Like Fun (With sujoyku) by Gene The Supreme (on 16. March 2025, 17:37) | 40 | 97 % |
| Kill Kill (Doubler Killer) by ICHTUES (on 28. August 2022, 06:00) | 62 | 98 % |
| [159] The Sum of All Indexing by W1DEMAN (on 9. November 2022, 09:59) | 22 | 97 % |
| Slitherlinked (Permaculture) by the_cogito (on 10. March 2025, 19:34) | 21 | 97 % |
| Big Brother (Landvermessung/Battenburg Hybrid) by MaizeGator (on 17. April 2025, 03:08) | 18 | 93 % |
| Going in Circles by antiknight (on 1. December 2022, 15:06) | 48 | 95 % |
| Lighthouses by IcyFruit (on 2. October 2025, 12:26) | 133 | 92 % |
| Messier 43 (Galaxy Region Sum Lines) by purpl (on 1. October 2022, 01:31) | 63 | 99 % |
| Japanese Anti Knight Double 2358 Sums by pandiani42 (on 28. June 2020, 17:21) | 22 | 90 % |
| CTC Tribute Arrow Sudoku by Lizzy01 (on 6. June 2021, 20:37) | 27 | 95 % |
| DEATH (collaboration) by grkles (on 4. January 2022, 22:20) | 45 | 99 % |
| Activated Japanese Sums by RockyRoer (on 12. November 2022, 13:36) | 22 | 95 % |
| Pandora's Renban by JeffWajes (on 18. January 2023, 21:12) | 49 | 97 % |
| Arrow Jungle by PotatoHead21 (on 18. August 2023, 11:49) | 24 | 93 % |
