(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 | |
|---|---|---|---|
 | 4-color killer sudoku #2 by Nylimb (on 3. April 2021, 04:45) | 113 |  99 % |
| Poles Apart (Remote Sums Chaos Construction) by tallcat (on 14. October 2025, 04:00) | 116 | 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 % |
| X---V*9.4 by NurglesGift (on 27. September 2025, 16:29) | 42 | 95 % |
| Yin Yang Sandwiches by flutchman (on 4. October 2025, 22:23) | 40 | 94 % |
| Foggy “Pair”-rows by Visumation (on 8. January 2025, 14:09) | 62 | 91 % |
| Intersections Sudoku by RockyRoer (on 16. July 2021, 14:00) | 20 | 93 % |
| [159] The Sum of All Indexing by W1DEMAN (on 9. November 2022, 09:59) | 22 | 97 % |
| Fujiyama by Myxo (on 14. December 2022, 14:24) | 37 | 99 % |
| Concurrence by Oddlyeven (on 31. May 2025, 01:34) | 19 | 94 % |
| Whisper Whisper by Jay Dyer (on 20. August 2022, 13:08) | 45 | 97 % |
| Going in Circles by antiknight (on 1. December 2022, 15:06) | 47 | 95 % |
| Messier 43 (Galaxy Region Sum Lines) by purpl (on 1. October 2022, 01:31) | 63 | 99 % |
| Cageless (X) Killer Sudoku no. 2 by Shinya (on 23. March 2020, 12:58) | 23 | 95 % |
| 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 % |
| Broken Square by PotatoHead21 (on 14. August 2021, 08:24) | 22 | 99 % |
| DEATH (collaboration) by grkles (on 4. January 2022, 22:20) | 43 | 99 % |
