The following are some of the languages spoken in the world of Greyhawk. They can be learned with the Speak Language skill, though exceptions may apply where noted. Unless your character speaks a particular language, assume that knowledge or recognition of it is OOC information.
Ordai: this tongue shared by the Wolf and Tiger Nomads is derived from Ancient Baklunish, but is most similar to the Low Baklunish dialects spoken by the Paynims. Influence from both Arapahi and Spaenhah can be seen in this language. Ordai has a number of dialects, and is also spoken by the Chakji and Guryik peoples of the north Drawmij coast. It is written using the Baklunish alphabet. Rare outside the nomadic tribes and the northern Drawmij coast, resources on it can only be found in large cities.
Osfaradd: a Low Baklunish dialect spoken primarily in Zeif, written using the Baklunish alphabet. Very rare outside Zeif, resources on it can only be found in very large cities.
Qualith: the written language of illithids, who do not speak but communicate telepathically. Each sentence takes the form of four parallel lines with textures that convey meaning when read by an illithid scanning its four tentacles along the lines simultaneously. Each of the four lines of script modifies the others, and only when taken as a whole is the full meaning intelligible. The script can be imprinted psionically onto almost any surface, but is nonmagical once created. Qualith is extremely difficult for non-illithids to read, and usually requires magic such as a comprehend languages spell to decipher. Attempting to non-magically decipher Qualith can be dangerous, as it is extremely informationally dense: if successful, a reader can gain insight on the writer's thoughts, its meaning, and even who the message was intended for, but failure can cause intense mental strain and even drive the reader mad. Some specially trained dwarves known as caradhakers (which loosely translates to "mindstalker") are able to grasp the basic meaning (but not the nuances) by running four fingers over the striations. Only caradhakers can learn Qualith, though other characters can gain bonuses to Decipher Script checks made against it by studying resources on it in large cities.
Rasol: primarily spoken by the Suel tribes of Hepmonaland. Derived mainly from Ancient Sueloise, Rasol is also heavily influenced by Olman, which supplied most of the proper nouns related to jungle life. Rasol has few phrases dealing with life outside the jungle environment, and many higher concepts are missing from the language. Interestingly, the Suloise creole that evolved in New Suel bears many resemblances to Rasol; a character fluent in either may learn the other for half as many skill points as normal. Like its cousin Amedi, Rasol's few written characters are from the Suloise alphabet. Very rare outside Hepmonaland, resources on it can only be found in very large cities.