OMAC (Buddy Blank) was created in 1974 by Jack Kirby and published by DC Comics. The character was created towards the end of Kirby’s contract with the publisher, following the cancellation of his New Gods series and was reportedly developed strictly due to Kirby needing to fill his contractual quota of 15 pages a week. As envisioned by Kirby, OMAC is essentially Captain America set in the future, an idea Kirby had toyed with some years earlier while at Marvel Comics, but had never realized.
Set in the near future (“The World That’s Coming”), OMAC is a corporate nobody named Buddy Blank who is changed via a “computer-hormonal operation done by remote control” by an A.I. satellite called Brother Eye into the super-powered One-Man Army Corps (OMAC).