Twice-Told-Tales: Ancient Adversaries and Fake Fossils

The so-called Caveman of Krypton arrived on Earth-One after living in suspended animation for untold eons. After facing both Batman and Robin, and soon after Superman, he was duped in servitude of a criminal masterminds and his henchman who pretended that be a caveman himself. After the crooks arranged for Kryptonite to be present to stifle Superman... it was the Caveman himself who brought the felons to justIce although he succumbed to Kryptonite poisoning himself and died.

His Earth-Two counterpart likewise remained inert for untold eons until scientists found him. This so-called Dawnman faced Superman and ultimately helped defeat the crIminal who had impersonated him and his boss to justice, although he died in the confrontation.