Overview
Codebusters is an event all about solving ciphers, or writing that has been encoded. There are generally three types of ciphers — ciphers where one letter is substituted for another (mainly Aristocrats and Patristocrats, and Xenocrypt, which is the same thing but in Spanish), math ciphers where numbers are used to represent numbers, and other ciphers (Pollux, Morbit, and Baconian) which use either As and Bs or Morse Code.
Codebusters is also a unique event in terms of its structure. 1) It is an event in which you compete in teams of three. 2) You cannot use a cheatsheet or binder, only the reference materials provided to you as part of the test. 3) There is a timed question. The timed question is always an aristocrat, and points are awarded based on how early you finish up to ten minutes.
The best thing about Codebusters is that it’s very formulaic. You know exactly the types of ciphers that will show up on the test, so as long as you practice those well, you should be prepared for success. The #1 site used by Codebusters for practicing aristocrats is cryptograms.org. You can play for speed and compete with other players. Other good links for practice can be found on the document on the right.
Below are some other good resources from ScioVirtual classes that teaches each cipher.
1️⃣ Single-Substitution Ciphers
- Website explaining different types of aristocrats - optional, but a good place to start if you want to learn more & dive deeper!
- https://www.nku.edu/~christensen/section 4 keyword ciphers.pdf
- Article explaining how to brute-force the key of a K3 cipher
⬆️ Aristocrats, Patristocrats, and Xenocrypt
⬆️ Caesar and Atbash
2️⃣ Math Ciphers
Letters to Numbers Quizlet
Letters to Numbers Kahoot
⬆️ Affine, Vigenere, and Hill overview
⬆️ In-depth Vigenere with practice problems
3️⃣ Other Ciphers
Pollux Solving Guide From Toebes
Morbit Solving Guide From Toebes
⬆️ Pollux and Morbit, which use Morse Code
⬆️ Baconian, which uses binary or As and Bs
Article on decryption & encryption
Solving Guide — Decrypting Railfence with an Offset
Practice test
There you have it! Every single type of cipher used in Division B competition is covered in at least one of these presentations. And actually, for Division B, you don’t even have to learn the Hill math cipher (this is Division C only), so that’s even less that you need to cover. The bulk of this event remains consistent practice, so make sure to use the links in the Event Resource Sheet to do so.