(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 | |
|---|---|---|---|
 | Renban Snakes by Chad (on 16. September 2024, 03:37) | 90 |  94 % |
| Hooked on Sudoku by Blashyrkh (on 18. June 2024, 10:42) | 98 | 94 % |
| Pentomino-Rundreise by Phistomefel (on 16. August 2020, 00:23) | 84 | 99 % |
| Steamed 'Bans (chaos construction with region sum clues) by SkepticalMario (on 5. September 2024, 00:00) | 91 | 97 % |
| Vice Versa (Region Sum Lines Sudoku) by Mr.Menace (on 23. June 2023, 09:30) | 97 | 93 % |
| Dutch Chaos Loop (CC) by gdc (on 15. July 2025, 14:32) | 103 | 99 % |
| Six-pack Linked Sudokus by Genomico (on 25. August 2020, 00:57) | 96 | 97 % |
| Disjunction Function by Jay Dyer (on 30. April 2024, 23:20) | 121 | 98 % |
| The Goldilocks Zone by marty_sears (on 14. September 2024, 15:04) | 162 | 99 % |
 | RAT RUN 37: Fruitful by marty_sears (on 13. May 2026, 01:00) | 291 | 98 % |
| Tapa Distiller by yureklis (on 18. August 2009, 21:08) | 51 | 93 % |
| 4 Gleiche by Luigi (on 1. October 2009, 17:10) | 39 | 91 % |
| Das versteckte Rätsel by Luigi (on 18. March 2010, 07:39) | 14 | 92 % |
| Verflixtes ABCtje by ibag (on 28. September 2011, 16:55) | 38 | 95 % |
| April ABCtjes Monat (3) - ABCtje mit und ohne X by Richard (on 20. April 2012, 12:00) | 38 | 92 % |
| Wichtelkalender 2014 - September: Materie-Antimaterie-Rundwege by Statistica (on 1. September 2014, 00:00) | 40 | 98 % |
| Wichtel 2015 (3): Maschinelle Synthese by wichtel (on 24. March 2016, 10:25) | 49 | 98 % |
| Inseln mit Hochhäusern, Teil 3 by pirx (on 8. December 2016, 20:00) | 45 | 98 % |
| OSTERN - Buchstabenrätsel by DocLogic (on 31. March 2020, 22:50) | 35 | 92 % |
| Two Sum Sudoku Finale - With Only One Numerical Clue! by ProwlingTiger (on 1. May 2020, 21:35) | 45 | 98 % |
