(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 | |
|---|---|---|---|
 | Boulder (Fillomino/Heyawake) by mathpesto (on 29. April 2023, 16:15) | 54 |  95 % |
| Overstuffed by Oddlyeven (on 19. June 2024, 00:43) | 25 | 96 % |
| Say, What Do Little Killers Eat? by RockyRoer (on 25. July 2024, 20:18) | 23 | 93 % |
| Suspicious Dwarf by Myxo (on 22. March 2023, 13:34) | 79 | 94 % |
| Counting Castles by marty_sears (on 18. February 2024, 03:37) | 159 | 96 % |
| Chaos Construction: 2nd Region X-Sums #1 (8x8) by Jesper (on 3. April 2022, 16:03) | 72 | 100 % |
| Loop Limit by marty_sears (on 24. September 2023, 13:49) | 108 | 97 % |
| Inseln mit Hochhäusern, Teil 3 by pirx (on 8. December 2016, 20:00) | 43 | 99 % |
| Differenzen zwischen Summen II by tuace (on 17. August 2018, 13:23) | 44 | 99 % |
| Amtsbeginn in Rätselhausen by Statistica (on 1. December 2019, 09:00) | 23 | 99 % |
| Udukos' breakfast by Qodec (on 14. October 2020, 20:49) | 26 | 95 % |
| Modular Killer by TotallyNormalCat (on 30. January 2021, 00:00) | 25 | 99 % |
| Very Friendly by PrimeWeasel (on 22. December 2022, 10:57) | 22 | 100 % |
| Monsoon by heliopolix (on 9. November 2023, 00:08) | 52 | 96 % |
| Prime Management by Dr Logic (on 21. December 2023, 16:43) | 22 | 91 % |
| Numbered Rooms Sudoku 2 by Lizzy01 (on 4. January 2022, 22:03) | 50 | 91 % |
| Japanischer Summen-Rundweg (knapp daneben, vielleicht) by Uhu (on 4. May 2017, 20:25) | 43 | 97 % |
| Snake Sum Sudoku 2 by Quarterthru (on 30. June 2020, 00:00) | 27 | 99 % |
| The 6 Sudokus of Christmas by Stavros96 (on 10. December 2020, 01:26) | 45 | 99 % |
| Yajilin Total/Regions 3 by Dandelo (on 4. January 2021, 22:10) | 25 | 99 % |
