Jak and Daxter: The Precursor Legacy is a platform video game. It follows the protagonists, a young teenager named Jak, as he tries to help his friend Daxter after he is transformed into an "ottsel", a fictional hybrid of an otter and a weasel. With the help of Samos the Sage, a master of the mysterious energy called 'Eco' created by an ancient race known as the Precursors, the pair learn that they must save their world from the rogue sages Gol and Maia Acheron, who plan to flood the world with "Dark Eco", a mysterious substance which corrupts all it touches.