Teoal Magic is a book defining a new brand of magic of the sea, specifically tailored to a Maztican campaign, but easily introduced in other campaigns. This book has a collection of spells and magic items tied to this magic, along with a few subclasses and other miscellaneous materials (including an updated Golden Ammonite creature!) related to such magic.
Teoatl is the magic of the Maztican seas related to shells, bioluminescence and other sea life.
In the Maztica campaign, there are two other new forms of magic known as pluma and hishna, which first appeared in the 1991 Maztica Campaign Boxed set. These new magic forms have also been updated in MZC1 The Maztican Campaign Guide (link below), but teoatl is an entirely new creation.
- from the publisher's blurb