Synostone (2017) is a Animation, Action & Adventure, Comedy, Sci-Fi & Fantasy, Kids series that follows the one who protects the world by becoming one with the spirits, 'Mask Masters' exists. world. Against the forces of darkness, the new power of the Mask Masters, 'Synostone' together. Unimaginable transformation robot. Synostone is not currently listed with streaming providers in your selected region, but availability can change over time. Fans of animation series may also want to explore similar titles below.