The Phantom Zone villain are back in Action 548 (Oct. 83), in a story by Cary Bates, Alex Saviuk, Vince Colletta and Pablo Marcos.
General Zod, Jax-Ur, Professor Vakox (in this story, rendered Va-Kox), and Faora have been tracking the one piece of jewel kryptonite, and find it. Concentrating their powers on it, Zod and Faora manage to escape to Earth, along with a couple of no-name villains. We do not see what happens with Jax-Ur and Va-Kox
At the same time, an alien race finds the remains of Argo City, and enter it to explore. They lean of the existence of Superman and Supergirl, and decide to head to Earth.
While the Phantom Zone villains prepare to attack Superman, he is busy dealing with some street hoods operating with Kryptonian technology.
The story continues int he next issue.