(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 | |
|---|---|---|---|
 | Half-Life² by ViKingPrime (on 10. February 2023, 15:32) | 18 |  96 % |
| Counterclockwise Killer by bodemeister (on 11. February 2023, 15:26) | 22 | 91 % |
| Microcircuit by Andrewsarchus (on 20. February 2023, 18:31) | 26 | 95 % |
| Nuclear Safety Inspector by ViKingPrime (on 10. March 2023, 14:00) | 12 | 93 % |
| X-Marks the Treasure Map by Maxentius (on 22. February 2023, 01:03) | 21 | 91 % |
| Max Arrows by antiknight (on 3. March 2023, 01:19) | 23 | 94 % |
| Stethoscope by JamesCullum (on 3. March 2023, 02:29) | 13 | 95 % |
| Round the Houses (Killer Loop) by tallcat (on 25. March 2023, 15:37) | 66 | 96 % |
| Clowns and Jokers by Die Hard (on 6. April 2023, 05:48) | 41 | 94 % |
| March of the Palindromes by EricRathbun (on 3. May 2023, 19:15) | 68 | 93 % |
| Waves by antiknight (on 7. April 2023, 03:07) | 33 | 91 % |
| Who Ordered The X-Sums? by RockyRoer (on 19. April 2023, 04:21) | 42 | 98 % |
| Dimorphism by Jay Dyer (on 19. April 2023, 10:34) | 94 | 98 % |
| Interference (Masyu/Chaos Construction/Cipher) by dumediat (on 22. April 2023, 18:32) | 38 | 96 % |
| Cornerstones [Sum Dot Infinity Loop] by wisty (on 26. April 2023, 22:15) | 16 | 96 % |
| Push Me Pull You by Die Hard (on 29. April 2023, 04:35) | 40 | 97 % |
| Corner Market by 99%Sneaky (on 16. May 2023, 16:59) | 48 | 93 % |
| Trebuchet (Slingshot Multi-Sudoku) by tallcat (on 5. July 2023, 08:00) | 56 | 97 % |
| Aid Hope In An Arrow Quotient by PotatoHead21 (on 10. July 2023, 15:58) | 16 | 93 % |
| Islands 3: Another Archipelagic Discovery by SamuPiano (on 21. July 2023, 01:44) | 16 | 100 % |
