(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 | |
|---|---|---|---|
 | Suguru Chaos Deconstruction #2: Kropki Edition by mathpesto (on 16. February 2022, 03:51) | 137 |  99 % |
| Triples - Killer Sudoku by Mr.Menace (on 7. May 2021, 13:47) | 52 | 95 % |
| Chaos Construction with Slitherlink clues #1 by Phistomefel (on 20. September 2020, 16:25) | 87 | 96 % |
| LM 2018 Countdown: U-Bahn mit Haltestellen by tuace (on 8. June 2018, 09:06) | 30 | 96 % |
| Two Gates by Qodec (on 15. October 2021, 22:22) | 70 | 99 % |
| Tree(3) by PulverizingPancake (on 4. November 2021, 19:25) | 74 | 97 % |
| Jealousy by mith (on 7. March 2022, 20:22) | 41 | 96 % |
| Killer Sudoku by PotatoHead21 (on 12. December 2021, 08:36) | 53 | 92 % |
| Sudoku Variants Series (371) - Sudoku Hangover by Richard (on 18. May 2022, 01:00) | 55 | 95 % |
| Eureka! by juggler (on 3. October 2024, 15:39) | 76 | 97 % |
| Broken Fence by Myxo (on 2. December 2022, 01:16) | 88 | 98 % |
| Killer Stern by tuace (on 6. February 2014, 19:30) | 48 | 98 % |
| Sandwich Sudoku - Club Sandwich by DiMono (on 31. December 2020, 15:20) | 19 | 96 % |
| Shooting Fish in a Cage by Strosahl (on 1. June 2021, 07:44) | 18 | 95 % |
| Rhombus Permutation by Tyrgannus (on 7. June 2021, 20:02) | 18 | 94 % |
| What's with the crust these days? by filuta (on 26. July 2021, 19:55) | 15 | 98 % |
| Cage² by GarlicBredFries (on 10. September 2021, 06:39) | 15 | 96 % |
| Portrait of a Little Killer by Strosahl (on 17. September 2021, 06:43) | 15 | 95 % |
| Petits Fours by fjam (on 10. January 2022, 16:41) | 17 | 91 % |
| Pared Down (Parity Arrow) by tallcat (on 22. January 2022, 22:44) | 51 | 92 % |
