(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 | |
|---|---|---|---|
 | Wichtels Rätselsommer 2024 (5): Wätsel-Weihnacht by wichtel (on 29. August 2024, 20:23) | 14 |  95 % |
| Thermal Doppelgangers by bodemeister (on 23. July 2025, 07:44) | 16 | 95 % |
| Wichtels Rätselherbst 2025 (2): Das heiße arktische Klima by wichtel (on 7. October 2025, 20:25) | 12 | 100 % |
| Red-Hot Ominoku by NXTMaster (on 5. December 2025, 00:00) | 16 | 98 % |
| Thinkies (Miracle Chaos Construction) by purpl (on 12. June 2022, 18:12) | 37 | 98 % |
| Liar Japanese Sums #7 - Ciphered Nurikabe by Niverio (on 1. December 2023, 00:53) | 46 | 100 % |
| Colossal Cave U-Bahn by Agent (on 29. April 2025, 09:00) | 40 | 100 % |
| Crystalline Entity by IcyFruit (on 22. May 2025, 13:23) | 67 | 91 % |
| Whirlpool by FryTheGuy (on 26. August 2021, 17:16) | 27 | 96 % |
| Shambhala by IcyFruit (on 20. October 2025, 11:34) | 86 | 97 % |
| Ten-Oh (10-Lines sudoku) by Qodec (on 21. May 2023, 18:31) | 77 | 97 % |
| Chaos Construction: Aquarium (2) by KNT (on 23. June 2022, 01:08) | 68 | 98 % |
| Chaos in the Knighttime by SenatorGronk (on 5. October 2022, 15:56) | 24 | 99 % |
| Berlin by zetamath (on 13. March 2023, 04:08) | 27 | 90 % |
| Four Alien Theorem (Build Your Own Killer Sudoku) by Agent (on 7. April 2023, 09:00) | 57 | 100 % |
| Times Square (CTC Secret Santa 2023) by alexc (on 11. March 2024, 01:34) | 11 | 95 % |
| Roller Coaster of Emotions by Agent (on 25. December 2024, 09:00) | 36 | 100 % |
| Sandwich Pseudoku by starwarigami (on 27. January 2025, 06:43) | 12 | 91 % |
| Constantinoqle (V-Bbhn witg Nestimg Ckues) by sfushidahardy (on 27. August 2025, 18:54) | 13 | 100 % |
| Chaos Construction: Miracle on 81 Cells by Playmaker6174 (on 17. September 2025, 07:00) | 39 | 98 % |
