Voltron: Defender of the Universe S01 E43 Voltron Frees the Slaves

Lotor once again is up to no good. First he conquers a new planet and dubs it Zarkonia. The people of Zarkonia are promptly enslaved and treated poorly, which Lotor hopes will draw Voltron...for he and Haggar have a little trap for their loathed arch enemy when he arrives.