Few common characteristics hold amongst the water genasi (also known as "sea kings" or "undines"), the most independent-minded of the genasi. Though usually descended from nereid or, more rarely, marid, water genasi are rarely raised by those that parented them, instead most often brought in by any of the wide variety of aquatic beings. While of course aquatic elves, tritons, and merfolk are common hosts, others have been raised by sahuagin or kuo-toa, still others by sharks or pods of dolphins, and a rare few by ixitxachitl or aboleths. As such, water genasi have amongst the widest breadth of personality and outlook of any of the genasi, and are quite unpredictable for it. The only trait that can be said to be nearly universal amongst the sea kings is a single-minded determination to accomplish great deeds and make a name for oneself, though even this has many exceptions amongst the subspecies.
This lack of a common bond between them means communities of water genasi are scarce, far more so than that of other genasi; an appreciable number of them go so far as to become hermits, dwelling in underwater caves with years between emergence. One water genasi for the most part feels no greater kinship for another than for any other kind, and second-generation water genasi are quite rare indeed; third-generation almost unheard of.
Water genasi, as do all genasi, usually bear some trait identifying their elemental heritage. Hair or skin of an aqua or pale blue shade is quite common, and often a water genasi's skin will be clammy, or covered in small scales. Many possess the dark eyes of a fish, or thin gill slits across the collar bones. For some, their hair constantly waves and flows as if they were always underwater, and still others have a deep booming voice akin to that of a whale. Water genasi will usually prefer dressing in clothing that doesn't impede motion underwater, but beyond that have no special inclinations towards any one style of clothing.
- Forgotten Realms Campaign Setting (3rd edition), pg.20
- Monsters of Faerûn, pp.71-72
- Races of Faerûn, pp.127-129
- Planeswalker's Handbook, pp.74-75