From the announcement:
One of the most fascinating regions of our own world is most assuredly Polynesia, a vast triangular area in the Pacific Ocean that encompasses Hawaii, New Zealand, Easter Island, Samoa, and Tahiti. This area is home to numerous creatures and beings that can be readily adapted for use in role-playing games and used either in conjunction with campaigns that have a South Seas flavor or as part of one-off encounters.
This sourcebook contains descriptions and game stats for more than a dozen monsters from this huge, varied region and notes on existing monsters that might also be encountered within it. It includes both actual creatures and those derived from myths, legends, folklore, reports from explorers, and other sources, and is inspired by the author’s personal adventures and research throughout the islands of Polynesia, notably Oahu, Hawaii, Kauai, Maui, Bora Bora, Moorea, Tahiti, and both main islands of New Zealand.
Creatures in this book include animated Tiki statues, Menehune little folk, lycanthropes like the Wereshark, Maero forest trolls, Monstrous Boars, Kumi and Kawekaweau lizards, Mo'o spirit guardians, Green Lady and Night Marcher undead, and illusion-using Weta insects. They have “Basic” OGL stats that can be used as-is or easily adapted for any d20-based games or other RPGs altogether.