(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 | |
|---|---|---|---|
 | Aquarium Sudoku by Sam Knott (on 20. June 2020, 13:07) | 26 |  93 % |
| Odd Trios Killer Sudoku by Quarterthru (on 19. September 2020, 12:00) | 26 | 99 % |
| Vector Field [Arrow, Killer] by Miky (on 28. April 2022, 19:43) | 23 | 96 % |
| Hopscotch (Remix) by Nordy (on 3. September 2022, 08:00) | 47 | 95 % |
| Puzzle Plaza (relative clones + cipher sudoku) by Aspartagcus (on 16. October 2022, 11:41) | 30 | 95 % |
| Peaucellier-Lipkin by Palfly Kampling (on 22. July 2023, 05:20) | 26 | 97 % |
| Hot Vaulted Banquet by Blobz (on 13. May 2024, 16:00) | 91 | 96 % |
| Parity Poopers by aleph-0 (on 29. February 2024, 12:59) | 22 | 99 % |
| GP24 Leftover: Japanische Summen + Magnetplatten by ibag (on 24. March 2024, 20:24) | 41 | 99 % |
| Fly Away on my Ziffer by DubiousMobius (on 7. August 2024, 11:54) | 25 | 97 % |
| Wraparound by mathpesto (on 29. June 2025, 23:31) | 24 | 95 % |
| Doppel Peas in a Pod by ralphwaldo1 (on 7. November 2025, 01:27) | 27 | 93 % |
| TLDR by Abdul the Killer (on 28. May 2024, 12:34) | 120 | 94 % |
| X---V*3 by NurglesGift (on 28. March 2025, 06:00) | 95 | 96 % |
| DSM 2023 Leftover: Full Rank Sudoku by uvo (on 5. July 2023, 12:00) | 59 | 92 % |
| 14 Givens by lepton (on 4. February 2024, 04:34) | 105 | 96 % |
| Sudokulike [DFoW] by Nurator (on 6. March 2025, 11:58) | 164 | 96 % |
| Snake in the City by Lizzy01 (on 28. November 2021, 14:24) | 41 | 95 % |
| Region Sum Lines Sudoku by Qodec (on 14. January 2022, 20:20) | 130 | 97 % |
| Hidden X-Sums by RockyRoer (on 8. August 2022, 17:48) | 39 | 99 % |
