| Mathematics | Broken RSA | 100 | |
| Mathematics | Modular Binomials | 80 | |
| Mathematics | Common Ground | 75 | |
| Mathematics | Successive Powers | 60 | |
| Mathematics | Chinese Remainder Theorem | 40 | |
| Mathematics | Quadratic Residues | 25 | |
| Mathematics | Real Eisenstein | 150 | |
| Mathematics | Unencryptable | 125 | |
| Mathematics | Ellipse Curve Cryptography | 125 | |
| General | Privacy-Enhanced Mail? | 25 | |
| General | Transparency | 50 | |
| General | Modular Inverting | 25 | |
| General | Modular Arithmetic 2 | 20 | |
| General | Modular Arithmetic 1 | 20 | |
| General | Extended GCD | 20 | |
| General | Greatest Common Divisor | 15 | |
| General | Lemur XOR | 40 | |
| General | You either know, XOR you don't | 30 | |
| General | Favourite byte | 20 | |
| General | XOR Properties | 15 | |
| General | XOR Starter | 10 | |
| Symmetric Ciphers | Forbidden Fruit | 150 | |
| Symmetric Ciphers | Paper Plane | 120 | |
| Symmetric Ciphers | The Good, The Pad, The Ugly | 100 | |
| Symmetric Ciphers | Pad Thai | 80 | |
| Symmetric Ciphers | Oh SNAP | 120 | |
| Symmetric Ciphers | Dancing Queen | 120 | |
| Symmetric Ciphers | Stream of Consciousness | 80 | |
| Symmetric Ciphers | Logon Zero | 80 | |
| Symmetric Ciphers | CTRIME | 70 | |
| Symmetric Ciphers | Bean Counter | 60 | |
| Symmetric Ciphers | Symmetry | 50 | |
| General | ASCII | 5 | |
| Introduction | Great Snakes | 3 | |
| Introduction | Finding Flags | 2 |
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