(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 | |
|---|---|---|---|
 | J-Sum Country Chaos by Cephalo (on 23. June 2023, 10:00) | 24 |  98 % |
| Medusa's Lair by XeonRisq (on 5. April 2024, 20:00) | 15 | 100 % |
| Wichtels Rätselsommer 2024 (5): Wätsel-Weihnacht by wichtel (on 29. August 2024, 20:23) | 11 | 95 % |
| SubwaYY to H... ? [Secret Satan #2] by Christounet (on 4. January 2025, 16:24) | 12 | 100 % |
| Invisible Killers by yttrio (on 10. March 2023, 21:32) | 37 | 98 % |
| Doppelcrypto Japanese Cave by KNT (on 3. October 2023, 18:10) | 41 | 100 % |
| Multi-sudoku: Orb 2 by DiMono (on 23. April 2021, 07:58) | 26 | 98 % |
| Roller Coaster of Emotions by Agent (on 25. December 2024, 09:00) | 26 | 100 % |
| Friendly X-Sums (Chaos Construction) by thoughtbyte (on 16. July 2022, 23:11) | 37 | 99 % |
| 4D Killer Sudoku by FryTheGuy (on 11. October 2021, 22:29) | 23 | 100 % |
| Arrow Forest by PotatoHead21 (on 28. September 2021, 09:51) | 14 | 90 % |
| Even Small Prime by FryTheGuy (on 13. December 2021, 16:28) | 25 | 99 % |
| The last call by filuta (on 18. April 2022, 17:38) | 25 | 94 % |
| Thinkies (Miracle Chaos Construction) by purpl (on 12. June 2022, 18:12) | 34 | 98 % |
| Enantiodromia (Yin-Yang Chaos Construction, 8x8) by thoughtbyte (on 3. August 2022, 00:05) | 24 | 99 % |
| Quicksort by filuta (on 29. June 2023, 14:15) | 10 | 100 % |
| Manhattan by wooferzfg (on 17. August 2023, 02:49) | 21 | 99 % |
| Japanese Japanese Sums Sums #1 by The Book Wyrm (on 30. November 2023, 22:11) | 28 | 98 % |
| Japanese Dominos by KNT (on 14. March 2024, 15:59) | 45 | 99 % |
| Japanese Sums Cave Cipher - KNT by ONeill (on 27. August 2024, 12:49) | 24 | 99 % |
