Arus is the first planet under Voltron's protection from the Galra Empire. Though firstly shown only to be a planet able to strive for life, later on it, it was known that local Arusians inhabit it. Arus seems to have a moon larger in size as compared to Earth's moon, noted that it could be how close it is as well. Though Earth and Arus share a lot in common, both are tremendously far away from each other, not even Earth's greatest telescope are able to find it. According to Shiro, Arus's location is in an unknown sector of the Universe where even Man knows doesn't know any of it's constellations.
- The Castle of Lions was on Arus for more than 10,000 years.
- Local Arusians have never went inside the castle until "The Fall of the Castle of Lions."
- Arus is the first planet under Voltron's protection and alliance.
- Local Arusians believe Allura is the legendary "Lion Goddess" and Voltron the "Mighty Robotic Angel".