The Cipher Challenge Contest
Four degrees of difficulty, from pen & paper to complex mathematical problems
Solved Level 1 challenge Caesar Encryption
Solved Level 3 challenge Sigaba Part 2
Solved Level 2 challenge Sigaba Part 1
Solved Level 1 challenge Strange Message from Thessaloniki
Solved Level 3 challenge Extended Handycipher — Part 6
Solved Level 2 challenge Spanish Strip Cipher — Part 1
Solved Level 1 challenge Number Sequence
Solved Level 3 challenge Extended Handycipher — Part 5
Four degrees of difficulty, from pen & paper to complex mathematical problems