Chemistro
Chemistro is an average super-villain armed with an "alchemy gun" that disintegrates and corrodes anything, and anyone who stands in his way.
He was in the Vault until the Breakout happened. He was with all of the prisoners getting their weapons and suits back in the Vault's armory after Living Laser sliced the door for them saying to everyone that "store's open!" As he grabbed his gear, he was punched in the face by Hawkeye, who also got his gear back.
When Iron Man blew up the Vault, Chemistro was able to escape.
He was later seen again as a member of the Masters of Evil recruited by Zemo for unknown reasons. He was with them waiting for the two Asgardians to return. The Enchantress had given Zemo the Norm Stones, which Chemistro jokingly stated about "how a bunch of rocks will help us take over the world?"
Then he was assigned to guard the Norm Stone in an unknown selected location from Hawkeye. He even reminded to his foe about what he done to him during the Breakout, which Hawkeye jokingly answered that he doesn't know about that. As they continue battle, the Norm Stone was activated along with all of them on Earth.
Hawkeye had finally beaten him by destroying his chemical gun which nearly melted his mask that forces Chemistro to take it off and got himself captured by one of Clint's special trick arrows.
Chemistro later appeared in Season 2 being pursued by the Enchantress and her Executioner after his loaction had been given to them by fellow Master of Evil the Living Laser. After reaching a dead end Chemisto confronted his persuers managing to melt the Enchantress's hand before she reformed it. In exchange for his life he gave the Asgardians the location of Arnim Zola but was betrayed when the Enchantress took his Alchemy Pistol and turned him into solid gold before taking his identity to infiltrate Avenger's Mansion and get close enough to Zemo to kill him.
In Ultima, Padro Lodo managed to free Chemistro from his gold prison and recruit him to the Organization, forcing the Enchantress to accept his membership to the Organization. Reluctantly, she agreed, and Chemistro is now a Grunt lieutenant in the Organization's Army.