(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 | |
|---|---|---|---|
 | 10X Lines by Oddlyeven (on 2. November 2025, 18:18) | 27 |  94 % |
| Mehrdeutige Rätsel - U-Bahn 3 by Zzzyxas (on 6. September 2017, 00:49) | 42 | 97 % |
| Sandwich Spread by Mark Sweep (on 5. November 2020, 10:00) | 17 | 90 % |
| Checkmate Sudoku by SenatorGronk (on 21. December 2020, 16:26) | 19 | 94 % |
| Nori Nori Killer Sudoku by MavericksJD (on 29. November 2021, 02:22) | 16 | 94 % |
| Serial Locks by twototenth (on 7. December 2021, 12:46) | 15 | 90 % |
| Crowded Square by jwsinclair (on 3. March 2022, 19:31) | 16 | 96 % |
| Berserk (slow thermo + german whispers sudoku) by Aspartagcus (on 18. March 2022, 21:28) | 19 | 92 % |
| Orb 4: It's All Gone Wrogn! by DiMono (on 14. June 2022, 20:32) | 29 | 99 % |
| Descending Madness 4 (Ambiguous Combination Constraint Arrows) by AnalyticalNinja (on 17. June 2022, 18:45) | 16 | 96 % |
| Jungle Japes [Indexing Killer Sudoku] by wisty (on 30. November 2023, 23:00) | 14 | 96 % |
| The devil's modular links by egubachu (on 8. April 2024, 21:58) | 16 | 92 % |
| Godoku by sfushidahardy (on 25. May 2024, 20:28) | 16 | 94 % |
| Neural Network by Tobias Brixner (on 20. August 2024, 16:35) | 14 | 92 % |
| Calamari by plasmath (on 28. December 2024, 02:00) | 18 | 92 % |
| Computational Maniac by SXH (on 2. January 2025, 04:54) | 20 | 92 % |
| Too Many Arrows by Md88keys (on 12. August 2025, 19:08) | 41 | 92 % |
| the cost of giving up by aqjhs (on 21. December 2025, 05:05) | 19 | 98 % |
| Tapa III by yureklis (on 24. March 2010, 22:44) | 92 | 95 % |
| Doppelt (Double Arrow) by tallcat (on 17. September 2021, 16:48) | 44 | 96 % |
