"Superman created by Jerry Siegel & Joe Shuster."

Clark Kent is dead! When grave circumstances cause Superman to leave behind his alter ego, an unimpeded Man of Steel must face his deadliest foe to date: Nimrod

Statements of responsibility vary from issue to issue.

"Originally published in single magazine form in Action Comics 1-10 and in book form in Superman/Action Comics volume 1: Superman and the men of steel, Superman

Tucked away high in the Himalayas, a long dormant evil has made these snowy mountaintops its home. Helspont, a decendant of the ancient alien race of Daemonites