(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 | |
|---|---|---|---|
 | Für Luca zum Geburtstag: Krypto-Inselrundweg by CHalb (on 4. November 2019, 09:29) | 30 |  95 % |
| 6x6 Hypercube by DiMono (on 18. February 2022, 23:40) | 28 | 95 % |
| [Fog of War Series] 3-2: Sequel to Portals by AstralSky (on 24. April 2023, 22:36) | 42 | 91 % |
| Wrogn Quasd by Sumanta(ANU) (on 20. August 2023, 13:18) | 32 | 90 % |
| Crossbow Training by Sniglett (on 29. December 2024, 02:18) | 31 | 94 % |
| Sudoku Variants Series (369) - Killer - Hidden Arrows Sudoku by Richard (on 4. May 2022, 01:00) | 81 | 97 % |
| Summenbild-Rundwegrätsel (1) by Uhu (on 3. November 2020, 20:29) | 44 | 98 % |
| Odd Cages by Phantou (on 18. July 2023, 22:40) | 46 | 93 % |
| Gegentakt by Myxo (on 27. July 2024, 11:33) | 108 | 97 % |
| Killer Sudoku: The Fearsome Twelves by Playmaker6174 (on 1. December 2022, 19:43) | 68 | 97 % |
| Unstable Seesaws (Collab with Piatato) by Cane_Puzzles (on 5. August 2025, 16:04) | 83 | 97 % |
| Pointer Arrow Parity Loop by yttrio (on 31. May 2025, 01:42) | 105 | 98 % |
| Yin Doubles Yang (Killer + Yin Yang) by damo_89 (on 8. June 2024, 17:24) | 160 | 97 % |
| Wichtel 2017 (9): 26341413052226052223243316041107251607 by wichtel (on 3. October 2018, 05:06) | 26 | 96 % |
| Snake Egg Sum Sudoku by Quarterthru (on 20. July 2020, 20:00) | 17 | 94 % |
| Juggling with the Twins (Partial Killer) by SudokuExplorer (on 2. October 2020, 02:00) | 33 | 91 % |
| Octothorpe by Konzert (on 27. February 2021, 20:23) | 20 | 91 % |
| Do Have A Go! by virtual (on 19. May 2021, 06:45) | 13 | 91 % |
| Kaged Knights by kuraban (on 27. June 2021, 02:50) | 35 | 98 % |
| Arrows of Central Tendency by mathpesto (on 14. November 2021, 21:48) | 16 | 91 % |
