Lester Dent
Lester Dent is credited as writer on 6 issues in grailworth's catalog, 4 issues of them across 3 series we value. Characters first seen in issues they wrote or drew include The Avenger, Ham, Algernon Heathcote "Smitty" Smith and Fergus "Mac" MacMurdie.
Characters they introduced
Every issue
Doc Savage Comics (1940) 1 issue
Shadow Comics (1940) 2 issues
Super-Mystery Comics (1940) 1 issue
Credits from the Grand Comics Database, CC BY-SA 4.0.