Terpenoids are enormously diverse. but our knowledge of their biosynthesis and functions is limited. Here we report on a terpene synthase (DdTPS8)-cytochrome P450 (CYP521A1) gene cluster that produces a novel C12 trisnorsesquiterpene and affects the development of Dictyostelium discoideum. DdTPS8 catalyzes the formation of a sesquiterpene discoidol. https://theplayfulcollectivees.shop/product-category/helmets/