The Great Massassi Temple, also known as the Great Temple of Massassi, Great Temple, Massassi Temple, Massassi Outpost, Massassi Base, or Base One, was built on Yavin IV by the Massassi to worship Naga Sadow, a Sith Lord who had enslaved and mutated the Massassi by the use of Sith alchemy. Thousands of years later, the temple had been abadoned, but was later housed as a base by the Rebel Alliance during the First Galactic Civil War. The Rebel Alliance had refitted the ancient-looking stone structure that notably contained a grand ceremonial chamber, a control room, and a vast hangar for starfighters.