(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 | |
|---|---|---|---|
 | Sunflower by RockyRoer (on 22. September 2021, 19:20) | 59 |  96 % |
| Confined Sandwich Chaos by PrimeWeasel (on 6. July 2022, 16:55) | 55 | 97 % |
| Never (Yajilin/Sudoku) by Wessel Strijkstra (on 6. November 2022, 17:41) | 52 | 95 % |
| Meidjuluk Fillomino Permaculture by Agent (on 27. June 2023, 09:00) | 87 | 96 % |
| Fillomino Sudoku by spxtr (on 29. August 2020, 08:26) | 30 | 95 % |
| 真笑Puzzles023--N-Sums Sudoku--Counter by cdwg2000 (on 5. February 2021, 17:45) | 30 | 100 % |
| Palindromaze by FinnishGuy (on 14. September 2021, 20:25) | 31 | 90 % |
| Remanence by Emphyrio (on 12. October 2021, 04:24) | 36 | 97 % |
| Killer Kropki Cages sequel by Ryx (on 28. March 2023, 06:45) | 33 | 91 % |
| Some Kind of Chaos by marty_sears (on 24. May 2024, 09:25) | 141 | 98 % |
| Slythering [Liar Japanese Sums Snake] by Christounet (on 4. June 2024, 07:54) | 30 | 100 % |
| Mictēcacihuātl (Castle Wall Delta + Directed U-Bahn) by sfushidahardy (on 22. May 2025, 08:11) | 28 | 95 % |
| Modular Fillomino by mathpesto (on 16. November 2024, 03:08) | 105 | 98 % |
| WPC 2016 Training - Pentominos by uvo (on 12. July 2017, 15:33) | 40 | 98 % |
| 10-in-9 Isolation Sudoku by Phistomefel (on 5. April 2020, 12:07) | 46 | 97 % |
| Sirius by jovi_al (on 19. February 2022, 03:07) | 41 | 98 % |
| Stairity - Chaos Construction by the_cogito (on 10. August 2022, 03:07) | 89 | 98 % |
| Safe Distances by Emphyrio (on 26. September 2022, 16:54) | 46 | 93 % |
| Displacement (Arrow Sudoku) by Phistomefel (on 10. May 2022, 19:07) | 103 | 98 % |
| Prime-Co Sweepers by XeonRisq (on 11. January 2023, 17:00) | 48 | 100 % |
