(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 | |
|---|---|---|---|
 | Slingshot Skirmish 5 - Siege Tactics by Allagem (on 10. May 2024, 13:37) | 34 |  95 % |
| Focus on Symmetry by Mad-Tyas (on 4. October 2024, 10:26) | 53 | 94 % |
| That Yarn Cat! by Sotehr (on 27. April 2025, 03:27) | 15 | 91 % |
| Vortex by NicoD (on 11. June 2025, 05:30) | 42 | 96 % |
| Someday We'll Meet Again by twototenth (on 29. August 2023, 08:00) | 104 | 97 % |
| Double Dip by zetamath (on 21. June 2022, 19:38) | 77 | 97 % |
| Competitive Tetris by Bremster (on 23. September 2022, 09:00) | 83 | 93 % |
| X-sums Parity Confetti by Playmaker6174 (on 24. January 2022, 08:32) | 32 | 99 % |
| Shuriken by crispy16 (on 24. May 2022, 19:43) | 41 | 94 % |
| Chaos Construction: Ariadne's Pet Dinosaur by Myxo (on 24. June 2023, 13:08) | 109 | 95 % |
| Killer X Sudoku #2 by Phistomefel (on 3. February 2020, 16:17) | 108 | 90 % |
| Akari Sudoku by Prasanna16391 (on 30. July 2020, 00:05) | 18 | 90 % |
| Rounded Killer Sudoku by RockyRoer (on 7. January 2021, 00:00) | 18 | 90 % |
| Maggot Sandwich by Piatato (on 8. August 2022, 11:07) | 33 | 97 % |
| Quarrowdruples by Joseph nehme (on 19. August 2022, 17:32) | 26 | 90 % |
| Liar Sum Before Digit 9 #1 by Playmaker6174 (on 2. April 2023, 13:07) | 17 | 93 % |
| Star Killer Part 3: Lunch Break by FischmitFahrrad (on 5. January 2024, 20:00) | 19 | 97 % |
| 200 Streams of Zetatude (Modifiers, Renban, Region Sum, Arrows, Anti-consecutive) by Chilly (on 28. December 2023, 14:25) | 17 | 93 % |
| World's Tallest Sandwich by Jreg (on 21. August 2024, 13:01) | 19 | 91 % |
| Clean Sweep [Parity Sweepers, Quads, Difference Dots collab with Mathgeek] by Malrog (on 7. November 2024, 17:06) | 16 | 92 % |
