Co-Creator of the Marvel Comics universe...although "Catalyst" might be a better term to describe him.
Together with an astounding group of artists (some, like Jack Kirby,
already legends in the field), he produced a memorable lineup of
characters and stories which, to this day, form the backbone both of the
comics line and various film and tv spinoffs.
Even the characters Lee didn't co-create (like Captain America and the Silver Surfer) were guided and shaped by Lee in his role as Editor into the versions we know and love today.
And credit where credit is due...Lee couldn't have done it without Kirby, Steve Ditko, Don Heck, Gene Colan, and the rest; while they, who had all done superb work without him, did their best work with him!
(C'mon, what post-Stan Lee Marvel characters have had any real success, outside of the 1975 revival of the X-Men, itself based on core characters created by Lee and Kirby?)
So, EXCELSIOR! to you, Stan the Man!