Real Name: Derek 'Deke' Mitchell
Occupation: Criminal
Marital Status: Single
Base of Operations: Gotham City
Height: N/A
Weight: N/A
Eyes: N/A
Hair: N/A
First Appearance: Detective Comics #587 (June 1988)
Created By: John Wagner, Alan Grant and Norm Breyfogle

A convicted murdered, Derek Mitchell escaped from jail seeking vengeance on Mortimer Kadaver, but was involved in an unfortunate accident on the way which turned him into a literally corrosive man. His entire skin burned with chemical fire which could eat through walls and floors or maim human flesh. His encounter with Kadaver left the latter with a handprint burned onto his forehead and left Mitchell inert, at least for a time, although he has surfaced at least twice more.