| From Russia with Love | 100 | Dec. 5, 2014, 11:50 p.m. |
| Trifid Cipher | 100 | Dec. 5, 2014, 12:09 a.m. |
| Snow White and the seven dwarfs | 108 | May 1, 2013, 10:20 p.m. |
| The Book Code: A Challenge for Bookworms | 100 | April 15, 2013, 11:40 p.m. |
| Reserve Hand Procedure — Part 1 | 110 | March 16, 2013, 1:50 p.m. |
| A hidden word | 200 | Jan. 6, 2013, 7:44 p.m. |
| How do you become a big cryptographer? | 100 | Dec. 30, 2012, 11:01 a.m. |
| Broadcasting and low exponent — RSA Attack | 1,142 | Dec. 23, 2012, 12:57 a.m. |
| Alice's Birthday Party (Part 2) | 1,126 | Dec. 23, 2012, 12:09 a.m. |
| Alice's Birthday Party (Part 1) | 1,126 | Dec. 22, 2012, 11:09 p.m. |
| Kaskade-S/T — Part 1 | 100 | Dec. 22, 2012, 7:34 p.m. |
| BCR code (Book-Caesar-RSA) | 1,231 | Dec. 21, 2012, 12:41 p.m. |
| Strange Message from Thessaloniki | 110 | Dec. 19, 2012, 11:41 p.m. |
| Classical Ciphers^3 | 100 | Dec. 19, 2012, 2:49 p.m. |
| Letter from the Alleged Countess Julie von Ortenburg | 100 | Dec. 19, 2012, 12:19 p.m. |
| A Secret Message from Castle Mansfeld | 100 | Dec. 19, 2012, 10:15 a.m. |
| Cracking SHA1-Hashed Passwords | 1,136 | Nov. 23, 2012, 11:22 p.m. |
| Factorization Cipher — Part 1 | 100 | Nov. 22, 2012, 11:53 p.m. |
| Pigpen with a twist — Part 1 | 100 | Nov. 21, 2012, 10:38 p.m. |
| Monoalphabetic substitution with camouflage — Part 1 | 100 | Nov. 18, 2012, 12:51 p.m. |
| Post-Quantum Cryptography: Unbalanced Oil and Vinegar System — Part 1 | 100 | Nov. 17, 2012, 5:54 p.m. |
| Letter to the Templars — Part 3 | 1,315 | Nov. 14, 2012, 3:49 p.m. |
| Letter to the Templars — Part 2 | 101 | Nov. 14, 2012, 3:14 p.m. |
| Letter to the Templars — Part 1 | 101 | Nov. 14, 2012, 3:10 p.m. |
| Affine Codes / Modulo Arithmetic with N / Extended Euclid | 100 | Nov. 13, 2012, 5:40 p.m. |
| ¿No Hablas Español? No problemo! | 100 | Nov. 13, 2012, 4:56 p.m. |
| Modified Caesar Cipher | 100 | Nov. 13, 2012, 12:50 a.m. |
| Grille Cipher | 100 | Nov. 12, 2012, 8:21 p.m. |
| A modified homophonic cipher with reduced alphabets — Part 2 | 100 | Nov. 12, 2012, 7:55 p.m. |
| A modified homophonic cipher with reduced alphabets — Part 1 | 100 | Nov. 12, 2012, 2:18 p.m. |
| Beaver Code | 101 | Nov. 11, 2012, 4:30 p.m. |
| Number Sequence — Part 4 | 100 | Nov. 11, 2012, 1:50 p.m. |
| Number Sequence — Part 3 | 100 | Nov. 11, 2012, 1:38 p.m. |
| Monoalphabetic Substitution | 100 | Nov. 11, 2012, 1:25 p.m. |
| Number Sequence — Part 2 | 100 | Nov. 10, 2012, 5:57 p.m. |
| Caesar Encryption | 100 | Nov. 10, 2012, 5:52 p.m. |
| Number Sequence | 100 | Nov. 10, 2012, 4:51 p.m. |
| Original Caesar Cipher | 100 | Nov. 10, 2012, 4:50 p.m. |