Skelectro

Skelectro (formerly Frank), was a major antagonist in season 1 until he became a protagonist alongside Skeletor. Frank was one of John's close friends in school. Soon after John transformed into Skeletor, Frank began hearing about the hero's heroic feats and became fascinated with Skeletor. A science project was coming up and Frank had the perfect idea. He collected a sample of residue left behind by Skeletor and took it to his own personal lab area. After rigorous experimentation he was able to create a machine that he believed would bestow him powers similar to that of Skeletor. Frank used the machine on himself and that proved to be a disaster as the machine horribly mutated Frank into a monster who bore a little resemblance to Skeletor. The mutation caused him to experience memory loss and outbursts of anger. He was granted his own superpowers and became a villain known as Skelectro. Skelectro spend the next while robbing stores and causing chaos around the city. Eventually he decided to go after Skeletor after finding the location of his house. Skelectro smashed into his house and confronted Skeletor. A tense confrontation between the two ended up with Skelectro remembering his past and Skeletor figuring out the identity of Skelectro. A bigger threat arose as Skeletor X was still on the loose and became more ruthless towards Skeletor and the people of the city. Skeletor and Skelectro decided to form an alliance against Skeletor X and the pair found him after a long search. Skeletor X hit Skelectro with a powerful beam of energy, mortally wounding him. This caused Skeletor to retaliate by doing the same to Skeletor X. The sheer power of the blast disintegrated the villain's body, killing him. Skelectro eventually died from his wounds and a saddened John began to arrange a funeral for his dead friend.

Powers
Skelectro's powers are similar to Skeletor's in a way but have some major differences. Skelectro can emit powerful beams of electricity from his appendages. He also has superhuman strength due to his extra limbs. Skelectro is more durable than a normal human but is still not as durable as Skeletor or Skeletor X. Unlike Skeletor, Skelectro lacks the ability to fly but makes up for this in his ability to jump high and climb fast.

Personality
Frank is your stereotypical nerd. He was intelligent and had a big interest in science and engineering. He liked to construct models using whatever he could find. Frank became fascinated with Skeletor and was determined to become like him. He spent a long time working on a way to gain superhuman powers similar to Skeletor's. After transforming into Skelectro, he began to lose his memory and his sanity. He became uncontrollably violent and destructive. After regaining his memory, he reverted to his old self again and aided Skeletor against Skeletor X.