(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 | |
|---|---|---|---|
 | Killer/Little Killer Sudoku - Find x! - Part 2 by ProwlingTiger (on 16. May 2020, 20:50) | 52 |  96 % |
| Überlappungssudoku by Richard (on 25. December 2009, 12:00) | 87 | 94 % |
| Spooky Action at a Distance by juggler (on 29. October 2025, 02:13) | 92 | 93 % |
| RAT RUN 16: Schrödinger's Rat by marty_sears (on 27. November 2024, 01:00) | 596 | 98 % |
| A Breath of Cold Glass by heliopolix (on 16. December 2024, 02:17) | 44 | 91 % |
| Twin Killer Sudoku V by Richard (on 16. March 2012, 12:00) | 72 | 93 % |
| Wichtel 2015 (8): Zahlenkoralle by wichtel (on 30. May 2016, 12:50) | 35 | 98 % |
| LM 2016 - Leftover: Mauerrundweg by CHalb (on 1. July 2016, 20:16) | 35 | 93 % |
| Battle With The Archers 17: Precision by Playmaker6174 (on 24. September 2021, 14:00) | 42 | 99 % |
| Starburst (Antiknight Arrows) by Florian Wortmann (on 19. June 2022, 15:06) | 50 | 90 % |
| BAD Values Snooker by Zombie Hunter (on 21. February 2023, 20:24) | 36 | 96 % |
| Seattle by ICHTUES (on 7. November 2021, 06:00) | 73 | 98 % |
| ECKIG - RUND - OVAL - Buchstabenrätsel by DocLogic (on 23. May 2020, 00:31) | 32 | 94 % |
| MiniClues by Mesmer (on 13. August 2020, 01:36) | 35 | 94 % |
| B-2 spirits by Joseph nehme (on 22. May 2021, 11:02) | 38 | 95 % |
| Worm on a Stick by ThePedallingPianist (on 20. December 2022, 01:17) | 78 | 92 % |
| Irregular Killer Sudoku 3 by Azure (on 12. April 2025, 09:28) | 40 | 95 % |
| Adventskalender 2025, Türchen 7 - Adventskerzen by Zzzyxas (on 7. December 2025, 07:00) | 36 | 95 % |
| The Diamond Sea (XY Differences Chaos Construction) by tallcat (on 10. May 2025, 06:00) | 195 | 98 % |
| Six-pack Linked Puzzles by Genomico (on 17. September 2020, 00:51) | 58 | 97 % |
