Romero
Romero is credited as penciller on 135 issues, inker on 135 issues, cover artist on 56 issues, colorist on 2 issues and others in grailworth's catalog, 5 issues of them across 4 series we value. Characters first seen in issues they wrote or drew include Desadia, Devil-Hunter, Zannarth and The Man-Monster.
Characters they introduced
Every issue
Comics Revue (1985) 1 issue
Eerie (1965) 1 issue
Haunt of Horror (1974) 2 issues
Credits from the Grand Comics Database, CC BY-SA 4.0.