The Thunderbolt is an episode of "The Herculoids" segments in the Space Stars show. It first aired 31 October 1981 on NBC.
Summary[]
Saiju, a benevolent creature with a voracious appetite, comes upon some electrical-charged rocks and turns into a living electrical monster upon eating them. The Herculoids learn that the effects of those rocks are temporary and try to get Saiju back to normal.