Use this skill to piece together the meaning of ancient runes carved into the wall of an abandoned temple, to get the gist of an intercepted letter written in the Infernal language, to follow the directions on a treasure map written in a forgotten alphabet or to interpret the mysterious glyphs painted on a cave wall.
Check: You can decipher writing in an unfamiliar language or a message written in an incomplete or archaic form. The base DC is 20 for the simplest messages, 25 for standard texts and 30 or higher for intricate, exotic or very old writing.
If the check succeeds, you understand the general content of a piece of writing about one page long (or the equivalent). If the check fails, make a DC 5 Wisdom check to see if you avoid drawing a false conclusion about the text. (Success means that you do not draw a false conclusion; failure means that you do.)
Both the Decipher Script check and (if necessary) the Wisdom check are made secretly, so that you can’t tell whether the conclusion you draw is true or false.
Creating a Cipher: You can use the Decipher Script skill to create a private cipher. This code system allows you (or anyone with the proper key) to record information without the risk of others reading it. Any document you create using your private cipher can be read only by you or someone who has the proper decoding information. Other characters with ranks in the Decipher Script skill can attempt to decipher the code. The DC for such a decoding attempt is 10 + your total skill modifier at the time that you create the cipher. (In effect, you “take 10” on a skill check to create the cipher, and those attempting to decode it make a Decipher Script check opposed by your take 10 result).
Encode or Decode Text: You can create a secret code that befuddles the reader. The DC is 20 for the simplest of messages, 25 for a standard text and 30 or higher for extremely lengthy or complex writings. The DC for someone using the Decipher Script skill to decode the text is equal to your check result. Anyone with a key to your code can read the text normally, although a separate Decipher Script check may be necessary if the original text was confusing and esoteric in the first place. Failure to decode the text has the same effects as for other uses of the Decipher Script skill.
Decipher Magic Scrolls (Epic): You can use the Decipher Script skill to decipher a written spell (such as a scroll) without using read magic. The DC is 50 + 5 × the spell level of the written spell. Only one try is allowed per written spell per day.
Action: Deciphering the equivalent of a single page of script takes 1 minute (ten consecutive full-round actions).
Creating a cipher takes a week of uninterrupted work. The first attempt to decipher a code system created by the Decipher Script skill requires a day of uninterrupted work, and subsequent retries each take a week’s time.
Deciphering the equivalent of a single page of coded script takes 1 hour.
Try Again: No.
You can attempt to decipher a private cipher more than once, but you must spend a great deal of time on each retry attempt. Each attempt to decipher a code beyond your first attempt takes a week’s worth of uninterrupted work. The first attempt to decipher a code system requires only one day’s work.
Special: A character with the Diligent feat gets a +2 bonus on Decipher Script checks.
Synergy: If you have 5 or more ranks in Decipher Script, you get a +2 bonus on Use Magic Device checks involving scrolls.
Source: Player’s Handbook (Page 71), Complete Adventurer (Page 98), Epic Level Handbook (Page 40), Races of Destiny (Page 147)