Sesquiterpene synthase that catalyzes the formation of sesquiterpenes and sesquiterpenoid alcohols (PubMed:24078339). Converts farnesyl diphosphate (FPP) to tau-cadinol (PubMed:24078339). Converts FPP to gamma-cadinene (PubMed:24078339). Tau-cadinol is the major product (PubMed:24078339). (2E,6E)-farnesyl diphosphate + H2O = diphosphate + tau-cadinol (2E,6E)-farnesyl diphosphate = (+)-gamma-cadinene + diphosphate Binds 3 Mg(2+) ions per subunit. Secondary metabolite biosynthesis; terpenoid biosynthesis. The Asp-Asp-Xaa-Xaa-Asp/Glu (DDXXD/E) motif is important for the catalytic activity, presumably through binding to Mg(2+). Belongs to the terpene synthase family.