Adventure Comics #333

The Legionnaires travel to the past to find out the story behind an ancient artifact which refers to a war between Earth and Krypton. The half that goes to Earth's past finds space travelers colonizing ancient Atlantis; the other half accompanies a group of Kryptonians who leave anti-scientific Krypton for Earth.

Characters: Ayla Ranzz, Brainiac 5, Chameleon Boy, Colossal Boy, Element Lad, Garth Ranzz, Luornu Durgo, Martha Kent, Mon-El, Phantom Girl, Saturn Girl, Superman, Thom Kallor