The Zeus Mk II ES (Essential) is a medium exploration spacecraft manufactured by Roberts Space Industries (RSI). An homage to the Zeus, the first commercially sold ship to come with a quantum drive, the Zeus Mk II retains the general shape of the original vessel but modernizes it for the 30th century SEY, introducing more width to allow for a larger living area. Each Zeus ES includes an advanced radar system to facilitate exploration alongside updated defensive capabilities to allow safer traversal along the frontier of the United Empire of Earth (UEE).