(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 | |
|---|---|---|---|
 | Fillomino Chaos Construction #2 by dennischen (on 7. June 2023, 18:15) | 39 |  98 % |
| Junction by grkles (on 22. May 2021, 03:53) | 22 | 99 % |
| U-Bahn under Tripleblock for polar by KNT (on 1. January 2024, 08:23) | 23 | 100 % |
| Satan Whispers by damasosos92 (on 19. February 2024, 16:42) | 26 | 95 % |
| LM 2017 Reste: Achterbahn (ohne Sicherheitsgurte) by pwahs (on 14. April 2017, 10:00) | 34 | 99 % |
| Chaos Construction: Border Sums by kolot (on 1. February 2022, 17:06) | 65 | 99 % |
| Chaos is a Club Sandwich (9X9) by SenatorGronk (on 19. February 2022, 23:49) | 34 | 97 % |
| Japanese Sum Cave Cipher #6: Fillomino by KNT (on 5. November 2022, 16:24) | 39 | 100 % |
| 1-N Chaos Deconstruction: Superfast Jellyfish by KNT (on 14. May 2022, 16:49) | 51 | 97 % |
| Wanda's Hex by fjam (on 25. September 2021, 11:00) | 15 | 96 % |
| Kashmir by lerroyy (on 29. March 2022, 20:26) | 44 | 96 % |
| Valve: Border Sums Chaos Construction by KNT (on 24. April 2022, 22:24) | 49 | 99 % |
| Country Road Fillomino #2 (12x14) by Jesper (on 25. October 2022, 08:02) | 40 | 100 % |
| Liar Japanese Sums #7 - Ciphered Nurikabe by Niverio (on 1. December 2023, 00:53) | 27 | 100 % |
| Japanese Sums #6: Volatility by Myxo (on 21. March 2024, 10:05) | 23 | 100 % |
| Thermo Sudoku by trivial171 (on 6. September 2020, 19:48) | 41 | 97 % |
| Chaotically Coordinated Arrows by Piatato (on 3. March 2022, 19:58) | 40 | 97 % |
| Watermill by lerroyy (on 15. May 2022, 22:44) | 24 | 96 % |
| Nary A'Dot by mormagli (on 2. February 2023, 22:42) | 24 | 93 % |
| Rock and a Hard Place (Chaos Construction) by tallcat (on 15. March 2023, 09:00) | 69 | 96 % |
