S1·E62 Mindbender

Dorn, Gloop, and Gleep are playing and discover an unearthed metal cylinder which contains an alien big-brained alien. When they release him he reveals himself to be a member of race that ruled Quasar thousands of years ago. The Herculoids seem powerless against his powers of telekinesis. Finally Zandor manages to defeat the alien by grabbing his amulet. When the Mindbender threatens to destroy him, Zandor tossed it back into the cylinder. It's a fake and when the alien is in the cylinder they seal it and put him back into stasis.