Shadowline (Epic Comics)
The Shadowline Saga is a comic book imprint from Epic Comics that was published in its original incarnation from 1988 to 1990. It was created and edited by Archie Goodwin.
The Shadowline Saga was Marvel's first attempt at creating a mature-themed line of superhero comics. Further, it was the first line produced by Epic Comics utilizing a pre-conceived shared universe concept. The central concept tied all of the titles together, allowing them to serve as one unified crossover. The line could either be read as individual title(s) or the entire line of titles could tell a much broader story when read together chronologically.
Read more about Shadowline (Epic Comics): Original Era, Second Era, See Also, Further Reading