Zzzax

Zzzax is a supervillain from Marvel comics. It was created in a freak accident when an electro-magnetic experiment exploded and absorbed the electronic impulses from the brains of nearby humans, killing them and giving the electricity sentience. Zzzax is made of living electricity, and thus is virtually indestructible. It can fire powerful blasts of energy, incinerating anything it touches. It also possesses superhuman strength, and can fly.

In order to exist, Zzzax must draw energy from the electro-psionic energy of people's brains. By doing so, it kills them, and increases its own intelligence. For some reason, Zzzax found this form of murder pleasurable, and undertook doing so whenever it had the chance. The only enemy it can't seem to kill is the Hulk, one of its common foes.