Everything

Language itself is a series of codes; folks who’ve been initiated into it (that is, folks who’ve learned the language) are considered members of the society in question. Some languages, however, are more exclusive and secretive than others. This Merit reflects your knowledge of a particular code known to only the “right people.”

Mages are secretive by nature, and so mage society is full of secret codes. Even Sleepers, though, have their own initiatory languages: military jargon, the Language of Flowers, various hand-signals, ciphers, and passwords employed by people who need to communicate with each other in ways no one outside their group can understand… except, perhaps, for those who’ve learned those codes through some “unauthorized” source.

As with the Merit: Language (p. 44), this Merit confers knowledge of a particular communication mode, which might not be in any way verbal. It could involve hand-signals, body postures, artwork, flags, symbolism, numbers, and so on. To uninitiated observers, that language appears to be gibberish (a word, incidentally, that refers to the coded writings of the alchemist Abu Musa Jabir ibn Hayyan); in many cases, a coded method of communication appears completely mundane unless you know what to look for, as with the encrypted artwork in The DaVinci Code.

One vital caveat: A character must have a very good in-game reason for knowing the things she knows. Learning a Secret Code Language requires some story-based foundation for that knowledge: elite military training, mind-reading, time among the group in question, etc. Fortunately, code languages tend to be utilitarian, revealing essential things in a general manner. (“I’m hungry,” “Kill him,” “This area’s forbidden,” etc.) Even so, codes may have subtleties that aren’t readily apparent; a single gesture or stressed syllable might mark the difference between Knock him out and move on quickly and Torture him to his least breath, no matter how long it takes.