Megawhatts are mischievous little aliens made of electrical energy. They stand about a foot high, have pointy legs, and have three fingers on each hand. They are black and yellow in color, with plus and minus symbols on their back. They also have a lightning bolt on their chest. The top of their heads electricity is emitted regularly. They exist only to cause trouble wherever they go. They grow stronger by absorbing electricity and can multiply if split in half or given enough power. They were defeated by Heatblast in the end after trapping them in the world's largest fish bowl.

In the episode, "Ben 10,000," it is revealed that Ben has acquired the ability to transform into the Megawhatt species which he cleverly named, "Buzzshocker."