Megavolt's greatest weakness is that he shorts out completely whenever he comes in contact with water. Because of this, Darkwing has defeated him numerous times when engaging him in battle.
As revealed in the episode "Clash Reunion", as a teenager, Elmo Sputterspark was fascinated with electricity and magnetism and, along with Drake Mallard, was tormented by the local school bully because of his "nerd" status. During a static-electricity experiment gone awry, Elmo's body became infused with so much electricity that he was able to harness its power and shoot it at any target he chose.
At the high school dance, he showed up in a yellow suit and tried to give himself the name Megawatt, but the band that was playing at the dance had the same name, so, to avoid ambiguity, he gave himself the name Megavolt. However, Drake Mallard had defeated him as Darkwing Duck, and since then, neither would see each other until many years later, and again on opposing sides.
Over the years, Megavolt became one of Darkwing's most formidable enemies, and would often be seen partnered up with Quackerjack. Both of them would also become part of Negaduck's group, the Fearsome Five.