S1·E38 The Thunderbolt

Saju, a creature with a voracious appetite, comes upon some electrically charged rocks, and eats them. He becomes a living electrical monster. But the Herculoids soon realize this is only temporary. While the others fill up the crevasse the rocks are in, Zandor lures Saju into a canyon. While trying to reason with him, Zandor is buried under a pile of rocks. Saju loses his electrical energy, and even helps Tara, Dorno, and the Herculoids get Zandor out.