- Rusk: the language of Kirupilov, a human language with some crossover and loan words from Arborean.
- Arborean: a human language with some crossover and loan words with Rusk. A related dialect is spoken on The Weeping Isle; it is close enough to Arborean that Arboreans and Islanders can usually understand each-other, with the occasional confusion over variant vocabulary.
- Dwarven: Sulterlander and Norturlander are closely related dialects sharing nearly-identical written script. A few Zimbruk in northern lands also know it. Goliaths speak a dialect of Sulterlander.
- Ephesian: an elven language commonly spoken by elves throughout the Viridian Sea; many traders and scholars learn it as well, and it is considered a hallmark of a good upper-class education. Ephesian gnomes share the language, and gnomes outside Ephesia usually learn it, to better communicate with them.
- Zimbruk: the official language of the Zimbruk Empire. Its script is unrelated to those of the other human languages around the Viridian Sea. Further complicated by differing conjugations, tenses, and verb-forms depending on the caste of the speaker and the one spoken-to, Zimbruk can be challenging to master for non-natives.
- Draconic: spoken in Salthor Eb, and related dialects spoken by a variety of monstrous humanoids throughout the Viridian Sea area; frequently studied by scholars.
- Ostrovot: an old human tongue nearly vanished from the Isles of Ostrovot; a handful of natives still keep it alive, and it exists in a few rare texts. Distantly related to Arborean.
- Pidgin: a trade-language used throughout the Viridian Sea area, and in particular by Zimbruk slavemasters when giving orders to foreign slaves. It borrows words from several languages.
- Infernal: spoken by a few well-educated folk on The Weeping Isle, but mostly as a means to study how to prevent new infernal incursions by scouring ancient infernal writings. Sages and scholars elsewhere in the Viridian Sea area occasionally know it.
- Celestial (Supernal): used in several important holy texts in Arbor, Kirupilov, and Ephesia. Virtually unknown in dwarven and dragonborn lands, and very rarely found in Zimbruk
- Deep Speech: a forbidden language found only in the rarest of texts, and known to a few scholars in Ephesia.
- Llandriath: an Elven language rarely spoken in Ephesia, and occasionally known to eladrin in Arbor with origins beyond the Viridian Sea area.
- Giant: A language spoken by monsters in the deepest wilds, virtually unknown to any but Goliaths (who sometimes learn it), and the occasional Sulterlander dwarf.
- Goblin: A language spoken by more common monstrous humanoids, and sometimes studied by travelers and rangers in Arbor particularly, rarely Kirupilov, Sulterland, and Norturland, and virtually never elsewhere.
- Primordial: Extremely rarely known by scholars and priests, and then typically only in writing (e.g., not spoken).
- Abyssal: occasionally known, by Norturlander dwarves in particular, who have contact with gnolls far to the northeast who speak it; a sahuagin dialect is sometimes known to Ostrovot Kirupilov and to sailors of The Weeping Isle. Demonic Abyssal is a dialect different enough to be a separate language, although with some similarities in script; a very few clerics trained in demon-hunting are familiar with it, although the knowledge is carefully guarded, and considered highly dangerous.