(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 | |
|---|---|---|---|
 | Angle of Attack by bodemeister (on 12. May 2024, 02:46) | 13 |  93 % |
| Liar Japanese Sums #9 - Cave (Aqre) by Niverio (on 1. August 2024, 19:24) | 27 | 100 % |
| Stolen Numerals XV*V by NurglesGift (on 9. August 2024, 20:17) | 78 | 91 % |
| Subway Roundabout by Niverio (on 21. August 2024, 22:25) | 41 | 98 % |
| ArrowThermoEntropy by Mad-Tyas (on 30. July 2025, 15:39) | 52 | 90 % |
| Killers and Palindromes by tenaliraman (on 3. January 2021, 06:45) | 41 | 98 % |
| #sudoku by matt383 (on 26. October 2021, 21:08) | 37 | 96 % |
| Cave Sums Sudoku by Christounet (on 2. January 2026, 20:39) | 35 | 98 % |
| Krypto-Kakuro-Koralle für pin7guin by ibag (on 6. September 2013, 00:00) | 63 | 99 % |
| Roman Lockout by Jay Dyer (on 19. February 2022, 23:16) | 24 | 94 % |
| Lookie Lookie (Doubler/Look-and-say/Renban) by dumediat (on 2. September 2022, 03:53) | 23 | 99 % |
| Siamese Coral (1) by KNT (on 6. March 2023, 02:36) | 51 | 100 % |
| TRICKY - Buchstabenrätsel / Letter Puzzle by DocLogic (on 16. April 2024, 15:44) | 32 | 97 % |
| ⊕ Deconstructed-RSL-Loop ⊕ by ElChiglia (on 20. April 2024, 07:15) | 49 | 92 % |
| Glowworms by mathpesto (on 17. November 2023, 00:03) | 67 | 95 % |
| Nuts and Bolts by KMD (on 15. March 2024, 10:18) | 56 | 95 % |
| Wichtel 2013 (10): Doppelschlangen-Höhle mit Doppellöwen by wichtel (on 30. May 2014, 10:32) | 28 | 99 % |
| Wichtel 2019 (11 und Schluss): Es soll nicht langweilig werden! by wichtel (on 6. November 2020, 20:01) | 18 | 100 % |
| In Between Disjoint Killings by tenaliraman (on 16. January 2021, 18:39) | 36 | 96 % |
| Kropkiominos by zetamath (on 30. May 2021, 00:17) | 40 | 97 % |
