| Playfair with hints about the grid | 100 | Feb. 24, 2023, 5:48 p.m. |
| The Syllabary Cipher – Part 2 | 1,222 | Feb. 17, 2023, 11:42 p.m. |
| Grille Cipher | 100 | Feb. 25, 2021, 6:30 p.m. |
| Letter to the Templars — Part 2 | 100 | Feb. 25, 2021, 2:05 p.m. |
| Polyhomophonic Substitution — Part 3 | 2,000 | April 7, 2020, 2:25 p.m. |
| Polyhomophonic Substitution — Part 2 | 1,824 | March 29, 2020, 5:36 p.m. |
| Polyhomophonic Substitution — Part 1 | 113 | March 29, 2020, 5:27 p.m. |
| Factorization Cipher — Part 1 | 100 | March 11, 2020, 7:51 p.m. |
| Polyphonic Substitution Cipher — Part 2 | 1,273 | March 11, 2020, 6:43 p.m. |
| Polyphonic Substitution Cipher — Part 1 | 1,223 | March 11, 2020, 6:24 p.m. |
| Molehunt (Part 2/3) | 100 | March 8, 2020, 11:03 a.m. |
| Molehunt (Part 1/3) | 100 | March 8, 2020, 10:46 a.m. |
| Number Sequence — Part 4 | 100 | March 8, 2020, 8:35 a.m. |
| Monoalphabetic Substitution | 100 | March 8, 2020, 8:30 a.m. |
| Number Sequence — Part 3 | 100 | March 8, 2020, 7:39 a.m. |
| Letter to the Templars — Part 1 | 100 | March 8, 2020, 7:35 a.m. |
| Number Sequence — Part 2 | 100 | March 7, 2020, 12:07 p.m. |
| Nils away on travel | 100 | March 7, 2020, 11:08 a.m. |
| Number Sequence — Part 6 | 100 | March 7, 2020, 10:02 a.m. |
| Number Sequence — Part 8 | 100 | March 7, 2020, 8:24 a.m. |
| Cryptanalysis Hacking Puzzles — Part 2 | 100 | March 7, 2020, 7:54 a.m. |
| Number Sequence — Part 10 | 100 | March 7, 2020, 7:48 a.m. |
| Autokey Cipher | 100 | March 7, 2020, 7:14 a.m. |
| The Einstein Enigma | 1,128 | March 5, 2020, 8:29 p.m. |
| Monoalphabetic Substitution with Nostradamus Flavor | 1,156 | March 1, 2020, 6:09 p.m. |
| Alice's Birthday Party (Part 1) | 1,084 | Feb. 29, 2020, 6:37 p.m. |
| Homophonic Encryption — Part 3 | 1,167 | Feb. 29, 2020, 8:11 a.m. |
| Homophonic Encryption — Part 4 | 1,167 | Feb. 28, 2020, 6:57 p.m. |
| Homophonic Encryption — Part 2 | 1,167 | Feb. 28, 2020, 6:19 p.m. |
| Homophonic Encryption — Part 1 | 1,166 | Feb. 28, 2020, 6:14 p.m. |
| Original Caesar Cipher | 100 | Feb. 23, 2020, 8:14 p.m. |
| Number Sequence | 100 | Feb. 23, 2020, 8:06 p.m. |
| Spanish Strip Cipher — Part 2 | 1,096 | Feb. 23, 2020, 7:21 p.m. |
| Spanish Strip Cipher — Part 1 | 1,096 | Feb. 23, 2020, 6:17 p.m. |
| Cracking SHA1-Hashed Passwords | 1,085 | Feb. 23, 2020, 3:09 p.m. |
| The Vatican Challenge — Part 4 | 10,000 | Aug. 23, 2019, 12:58 a.m. |
| Catherine of Aragon's Letter to King Ferdinand, her Father (1509) | 2,000 | Dec. 11, 2018, 3:50 p.m. |
| Letter to the Templars — Part 3 | 1,095 | Nov. 22, 2018, 3:43 p.m. |
| The Vatican Challenge — Part 2 | 1,000 | April 16, 2018, 4:42 p.m. |
| Letter from the Alleged Countess Julie von Ortenburg | 100 | March 29, 2018, 12:47 p.m. |
| From Russia with Love | 100 | March 29, 2018, 9:15 a.m. |
| Advent-Challenge — Part 1 | 101 | March 28, 2018, 6:18 p.m. |
| ¿No Hablas Español? No problemo! | 100 | March 28, 2018, 5:57 p.m. |
| Playfair Encryption | 100 | March 28, 2018, 5:48 p.m. |
| The Vatican Challenge — Part 1 | 2,000 | March 12, 2018, 3 p.m. |