The Black Paladin is the eleventh and last episode of Season One.
With Allura captured, the rest of the team are quick to mount a rescue mission. Almost as soon as they arrive, Zarkon activates a particle barrier, trapping them inside. Voltron is quick to destroy most of the Galran forces, but are somehow forcibly separated by Zarkon and Haggar.
The Paladins scramble to rescue Allura while Shiro is suddenly ejected from the Black Lion. As he tries to get back to his lion, he encounters Haggar and is easily overwhelmed by her magic, only to be rescued by Allura and Hunk.
Zarkon moves to claim the Black Lion, revealing himself as the original Black Paladin of Voltron, but Keith intercepts him and the pair battle. Zarkon easily overpowers Keith’s Red Lion with his mastery over the black Bayard, being able to form a multitude of different weapons in an instant. Before Zarkon can kill Keith, Shiro rescues him with the Black Lion.
The Castle-ship is unable to form a wormhole to escape, until one of Zarkon’s own commanders suddenly destroys the sentries guarding the barrier generator and shuts it down. As they attempt to escape through a wormhole, Haggar hits it with her lightning, causing the portal to become unstable. The lions are separated from the Castle-ship in the wormhole, each of them falling to parts unknown.