DC Exploration: Aethyr the Oversoul

Who is He?

Aethyr is a relatively obscure Superman character from the Pre-Crisis period having only three appearances during the Pre-Crisis time period as well as a few more lately. Aethyr was formed during a galactic collision where the souls of the inhabitants of multiple galaxies were ignited in rage at their sudden demise, a rage that fused them into a singular godlike being. This being appears to people alternatively as a purple dragon creature or as a talking crystal heart and is basically the reason for the Phantom Zone. 

How Powerful is He?

To make a long story short, he's one of the most powerful characters in the Superman franchise in particular having created the Phantom Zone around himself. He's a Fourth World Entity, meaning that he's stronger than basically any third world entity including any main member of the Justice League but below the fifth world entities like the Imps. What's a lot more interesting is how he compares to other Fourth World Entities.

Aethyr is comprised of "a billion-billion" souls with individual souls in DC being a power source for beings in the Godsphere, the Fourth World and each soul in the Godsphere being able to create its own universe. He created Phantom Zone and controls it purely via his will, the Phantom Zone being a many layered conceptual prison universe he keeps people within. This is a pretty impressive feat and definitely puts him above most Fourth World Entities. That said, the Phantom Zone is just a small part of the overall Underworld, and there's nothing suggesting he scales to the manipulation of one of the eight divine realms overall meaning he's more than likely weaker than the high tier members of the Godsphere like Darkseid and Zeus. If I had to say where he is, Aethyr is roughly a Mid-Fourth World Tier character, on the same level as many of the Gods of Skyland or the rules of individual provinces of Hell. 

What are His Powers?

Unsurprisingly given his origin, Aethyr is known for his soul and spiritual manipulation. He created the ghostly realm of the Phantom Zone outside spacetime "at the edge of thought, where outerverse and autoverse meet" and can completely control it and anything inside it with his thoughts. He can also send people out of it, though whether he can draw people into it is unknown. Aethyr can freely manipulate all the souls of the Phantom Zone which should at least include the quadrillion souls that comprise him, but more than likely includes infinite souls given that the Phantom Zone is connected to infinite universes. 

Aethyr is also know for his ability to use fusion and spiritual draining as anyone who gets close to him has their spirit, their individuality siphoned until they become one with Aethyr the Oversoul. This even worked on Mr. Mxyzptlk, though given the Imp had been forbidden from using his powers by the other 5D Imps, this might not actually mean much.Aethyr normally remains at the center of the Phantom Zone which is viewed as literally being Aethyr's mind, a space generated by the interaction of Aethyr's self and the outside world. 

What are His Weaknesses?

Aethyr's weaknesses are mostly mental than "physical" so to speak. Comprised of billion-billion souls, Aethyr was massively internally divided with Mxyzptlk explaining that it was like "Godhood Bi-committee" mostly acting off self-protective instinct with Mxyzptlk summarizing it as "the most powerful force in the universe an' all he knew was how to protect himself!" Aethyr also alternates between periods of being "awake" and being "dormant" where it is possible to sneak past him, though still extraordinarily difficult as none of the souls trapped in the Phantom Zone have ever been able too. 

Finally Aethyr is unable to harm someone if he's unable to find any despair within them for some reason, with Superman being able to fly right through Aethyr's center without being assimilated. Though as this is Superman, the symbol of Hope itself, your mileage may vary on who else would be able to do so with no one else ever trapped in the Phantom Zone besides Superman ever being able to escape. 

In conclusion Aethyr is an extraordinarily powerful entity and one of the strongest Superman characters, being a mid fourth-world tier enemy though wouldn't do very well against the other strongest Superman characters. I think someone like Lord Satanus or Kismet would just overpower the ghost dragon, and while Lady Blaze would be a lot more fair, I do think she would be able to decieve Aethyr. That said he should be given a lot of credit for treating End of Pre-Crisis Superman as just a thought in his mind universe. 

As a final fun trivia note, Aethyr is not evil. In Wonder Woman 778, Wonder Woman is battling the Kryptonian Criminal Xa-Du in the Phantom Zone when Aethyr appears, stops Xa-Du and gives Wonder Woman and friends safe access to leave the Zone to pursue Janus like they were trying too.