Years ago, the Voltron Force ultimately defeated Prince Lotor, resulting in h...
Voltron: The Third Dimension
Season 1 Episode 9: Voltron vs. Dracotron
Lotor has Haggar summons five robot dragons, which can form the powerful Dracotron, to destroy the Voltron Force. But Lotor and Haggar soon lose control and must have a brief alliance with the Voltron Force to defeat Dracotron.