When Adolf Hitler personally ordered that Atlantis be infected with the Copper Plague, Kornstalk was recovered to head this operation. An undersea base was constructed with electrodes that filled the oceans surrounding Atlantis with copper particles that made the Atlanteans deathly ill. When summoned back to Atlantis by Princess Fen, Namor was soon contacted by Kornstalk who ordered Namor's surrender in exchange for a cure.