(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 | |
|---|---|---|---|
 | Scaffolding (Arrow Sudoku) by emmettcito (on 24. April 2021, 21:24) | 37 |  95 % |
| Bedazzled by GarlicBredFries (on 7. May 2021, 18:54) | 16 | 92 % |
| Welcome To Mars (Anti-knight/Thermo Sudoku) by EliasKar (on 8. May 2021, 19:53) | 35 | 92 % |
| Stostone - Aoi's Big Birthday by athin (on 15. May 2021, 07:00) | 15 | 98 % |
| What's In The Box by Quarterthru (on 11. May 2021, 12:00) | 23 | 91 % |
| Frankfurt by Mark Sweep (on 28. May 2021, 10:00) | 28 | 99 % |
| Mathlements by Qodec (on 7. June 2021, 19:47) | 52 | 99 % |
| Ricochet (Arrow Killer) by tallcat (on 11. June 2021, 16:01) | 56 | 91 % |
| Arrow Australis by jacksongriggs (on 24. June 2021, 22:43) | 17 | 92 % |
| Category 5 Hurricane by Polycarp (on 14. July 2021, 20:14) | 15 | 90 % |
| Roller Coaster mit Extras 21 by Uhu (on 22. July 2021, 17:27) | 33 | 98 % |
| Big Purple Creature by PulverizingPancake (on 6. August 2021, 06:46) | 26 | 94 % |
| Firefly by SSG (on 11. August 2021, 07:07) | 17 | 91 % |
| The Locked Chain - can you break the chain? by purpl (on 23. August 2021, 17:25) | 37 | 98 % |
| Parity Party XXI, "aPProXimat" by glum_hippo (on 12. September 2021, 23:59) | 20 | 96 % |
| In or Out? (Between Lockout Ambiguity) by tallcat (on 1. October 2021, 16:33) | 49 | 97 % |
| 5K 5A by Joseph nehme (on 15. October 2021, 15:11) | 39 | 97 % |
| Astarboard Steerer by the_cogito (on 18. October 2021, 15:12) | 15 | 91 % |
| X12 Cages by Quarterthru (on 1. November 2021, 06:02) | 22 | 92 % |
| A Shot in the Dark (Whisper Arrow) by tallcat (on 11. November 2021, 15:28) | 47 | 97 % |
