Parasite

Born into the gritty, morally complex world of DC's Copper Age, Parasite first emerged in John Ostrander and Luke McDonnell's Suicide Squad #1 in 1987 — a debut that immediately signals this is a character who runs in dangerous, consequential company. With nearly four decades of appearances stretching into 2025, Parasite has proven a lasting presence in the Superman corner of the DC universe, sharing pages with the Man of Steel himself alongside Clark Kent, Lois Lane, and Jimmy Olsen across titles like Adventures of Superman and Superman Adventures. That one collector-recognized key issue in the catalog is a flag worth heeding for anyone building a serious run. Nineteen appearances may sound modest, but for a villain with this kind of staying power and pedigree, every issue counts.