(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 | |
|---|---|---|---|
 | Watermill by lerroyy (on 15. May 2022, 22:44) | 29 |  97 % |
| Subway To Hell by Piatato (on 27. January 2024, 15:45) | 26 | 100 % |
| This Thing [Antiknight Series] by wisty (on 10. December 2024, 22:23) | 38 | 96 % |
| Chaos Construction: Border Sums by KNT (on 24. April 2022, 22:24) | 55 | 99 % |
| Chaos is a Club Sandwich (9X9) by SenatorGronk (on 19. February 2022, 23:49) | 36 | 98 % |
| Star-Crossed Sandwiches by DarthParadox (on 25. January 2024, 01:26) | 27 | 92 % |
| Zodiac Project: Cluster of Galaxies by Prof.Dori (on 6. November 2024, 00:51) | 26 | 99 % |
| Crypto Japanese Cave (Fillomino) by KNT (on 5. November 2022, 16:24) | 43 | 100 % |
| Sadism by grkles (on 17. October 2022, 13:05) | 58 | 96 % |
| Tetrafolium by Myxo (on 17. February 2025, 15:40) | 70 | 97 % |
| Knapp daneben Twin Killer II by Richard (on 1. January 2010, 12:00) | 36 | 94 % |
| Watchtower sudoku by Lizzy01 (on 1. August 2022, 10:24) | 19 | 95 % |
| Colossal Fillomino with Sandwich Sudoku by MagnusJosefsson (on 28. September 2022, 15:50) | 66 | 100 % |
| Rock and a Hard Place (Chaos Construction) by tallcat (on 15. March 2023, 09:00) | 79 | 96 % |
| Colossal Tapa and Chaos (ft. KNT) by wooferzfg (on 6. May 2023, 06:00) | 39 | 100 % |
| Liar U-Bahn by Myxo (on 8. June 2023, 12:47) | 34 | 99 % |
| Entropic Loop Chaos by yttrio (on 9. February 2024, 19:28) | 73 | 96 % |
| Trail of Prometheus (Secret Satan) by Agent (on 14. January 2025, 09:00) | 16 | 100 % |
| Wheel of Arrows (arrow + little killer sudoku) by Aspartagcus (on 6. April 2021, 12:20) | 45 | 95 % |
| Ciphered Japanese Sums - KNT by Niverio (on 22. April 2023, 12:18) | 40 | 100 % |
