With Friends Like You - S2.E16

Coran is showing the Voltron Force space images of the planet Philos - an oddity in that it's a planet that orbits and acts like a comet. Ineterrupting their space lesson is a skull tank, which lands on Arus with a white flag raised. Though skeptical, the team has to check it out. Alliance guards escort the pilot of the tank out, which is an alien who claims to be from Philos. Lance wants to just lock him up right away, but Allura gives the stranger a chance.