| Hill Cipher with Sudoku Key | 100 | Nov. 15, 2022, 7:04 p.m. |
| The Syllabary Cipher – Part 1 | 133 | Oct. 30, 2022, 2:12 p.m. |
| Alberti Challenge — Part 1 | 104 | April 22, 2022, 3:14 p.m. |
| Trifid Cipher | 100 | Oct. 25, 2021, 8:01 p.m. |
| Nils away on travel | 100 | Oct. 24, 2021, 3:29 p.m. |
| Homophonic Encryption — Part 1 | 1,122 | Oct. 23, 2021, 2:28 p.m. |
| The Last Note | 100 | Oct. 9, 2021, 1:42 p.m. |
| Letter from the Alleged Countess Julie von Ortenburg | 100 | Oct. 9, 2021, 12:57 p.m. |
| Number Sequence — Part 7 | 100 | Oct. 8, 2021, 6:29 p.m. |
| Multilingual Monoalphabetic Substitution | 100 | Oct. 8, 2021, 3:53 p.m. |
| Homophonic Encryption — Part 4 | 1,122 | Oct. 8, 2021, 12:12 p.m. |
| Homophonic Encryption — Part 3 | 1,122 | Oct. 8, 2021, 12:08 p.m. |
| Homophonic Encryption — Part 2 | 1,122 | Oct. 8, 2021, 11:34 a.m. |
| Number Sequence — Part 9 | 100 | May 14, 2021, 9:08 p.m. |
| Number Sequence — Part 10 | 100 | May 14, 2021, 8:41 p.m. |
| Zodiac Cipher | 100 | May 12, 2021, 2:35 p.m. |
| Enigma Messages with Repeated Letters — Part 5 | 100 | May 12, 2021, 12:55 p.m. |
| Enigma Messages with Repeated Letters — Part 4 | 100 | May 12, 2021, 11:50 a.m. |
| Enigma Messages with Repeated Letters — Part 3 | 100 | May 12, 2021, 10:30 a.m. |
| Enigma Messages with Repeated Letters — Part 2 | 100 | May 12, 2021, 9:50 a.m. |
| Enigma Messages with Repeated Letters — Part 1 | 100 | May 11, 2021, 10:37 p.m. |
| Find the right route — Part 1 | 101 | May 10, 2021, 10:57 p.m. |
| The Book Code: A Challenge for Bookworms | 100 | May 10, 2021, 9:17 p.m. |
| Classical Ciphers^3 | 100 | May 10, 2021, 1:39 p.m. |
| Playfair Encryption | 100 | May 9, 2021, 10:46 p.m. |
| Double Columnar Transposition | 100 | May 9, 2021, 10:05 p.m. |
| Pigpen with a twist — Part 1 | 100 | May 9, 2021, 3:07 p.m. |
| Wheatstone Cryptograph — Part 1 | 106 | May 9, 2021, 10:32 a.m. |
| Playfair with hints about the grid | 100 | May 7, 2021, 11:57 p.m. |
| ADFGVX — Part 2 | 100 | May 7, 2021, 12:22 p.m. |
| ADFGVX — Part 1 | 100 | May 6, 2021, 10:01 p.m. |
| ¿No Hablas Español? No problemo! | 100 | May 6, 2021, 9:25 p.m. |
| A hidden word — Part 2 | 100 | May 6, 2021, 9 p.m. |
| From Russia with Love | 100 | May 6, 2021, 6:47 p.m. |
| One-Time Pad with Flaws | 100 | May 6, 2021, 3:02 p.m. |
| M-138 — Part 2 | 1,094 | May 6, 2021, 10:57 a.m. |
| M-138 — Part 1 | 100 | May 6, 2021, 8:41 a.m. |
| Number Sequence — Part 5 | 100 | May 5, 2021, 11:16 p.m. |
| A modified homophonic cipher with reduced alphabets — Part 2 | 100 | May 5, 2021, 9:59 p.m. |
| Cryptanalysis Hacking Puzzles — Part 2 | 100 | May 5, 2021, 8:55 p.m. |
| A modified homophonic cipher with reduced alphabets — Part 1 | 100 | May 5, 2021, 8:49 p.m. |
| Molehunt (Part 1/3) | 100 | May 5, 2021, 1:20 p.m. |
| Molehunt (Part 2/3) | 100 | May 5, 2021, 1:14 p.m. |
| Image Noise | 100 | May 4, 2021, 2:16 p.m. |
| A hidden word | 100 | May 4, 2021, 1:47 p.m. |
| Number Sequence — Part 6 | 100 | May 4, 2021, 10:07 a.m. |
| Number Sequence — Part 4 | 100 | May 4, 2021, 10:04 a.m. |
| Reserve Hand Procedure — Part 1 | 100 | May 4, 2021, 9:56 a.m. |
| Modified Caesar Cipher | 100 | May 4, 2021, 8:32 a.m. |
| Autokey Cipher | 100 | May 3, 2021, 8:26 p.m. |
| How do you become a big cryptographer? | 100 | May 3, 2021, 8:03 p.m. |
| Grille Cipher | 100 | May 3, 2021, 6:30 p.m. |
| Number Sequence — Part 8 | 100 | May 3, 2021, 5:56 p.m. |
| Advent-Challenge — Part 1 | 100 | May 3, 2021, 5:52 p.m. |
| Snow White and the seven dwarfs | 100 | May 3, 2021, 2:34 p.m. |
| Factorization Cipher — Part 1 | 100 | May 3, 2021, 1:13 p.m. |
| Cracking SHA1-Hashed Passwords | 1,083 | May 3, 2021, 1:03 p.m. |
| Letter to the Templars — Part 3 | 1,086 | May 3, 2021, 12:59 p.m. |
| Affine Codes / Modulo Arithmetic with N / Extended Euclid | 100 | May 3, 2021, 12:50 p.m. |
| Monoalphabetic Substitution | 100 | May 3, 2021, 12:20 p.m. |
| Letter to the Templars — Part 2 | 100 | May 3, 2021, 11:18 a.m. |
| Letter to the Templars — Part 1 | 100 | May 2, 2021, 10:08 p.m. |
| Number Sequence — Part 3 | 100 | May 2, 2021, 9:46 p.m. |
| Beaver Code | 100 | May 2, 2021, 9:39 p.m. |
| Caesar Encryption | 100 | May 2, 2021, 8:41 p.m. |
| Number Sequence — Part 2 | 100 | May 2, 2021, 8:18 p.m. |
| Original Caesar Cipher | 100 | May 2, 2021, 8:16 p.m. |
| Number Sequence | 100 | May 2, 2021, 8:13 p.m. |