Superman in the New 52
Superman is one of the characters that has undergone a lot of changes in the DC Comics Rebirth initiative. His story-line has seen quite a bit of upheaval. Let’s try to get you up to speed without too much unneeded detail.
In the New 52 we saw a younger Superman. The pre-Flashpoint Superman had vanished from the timeline. This younger Superman had only recently become a superhero. He was not the squeaky clean boy scout type. He would not only fight against criminals, but against any injustice, even if it meant breaking the law, battling a corrupt government, or losing his temper with the police.
He had also lost both of his Earth parents before taking a job at the Daily Planet. He did not have the Kents guiding him. This New 52 version actually started a relationship with Wonder Woman.
As a result of DC Comic’s Convergence story-line all previous existing universes were brought back and merged into one timeline. That means the pre-Flashpoint version of Superman existed alongside the New 52 version.
Superman in Rebirth
The pre-Flashpoint version of Superman was married to Lois Lane and they had a son (Jonathan Kent). Jonathan inherited many of his fathers powers and abilities. They decided to remain under the radar in this new merged universe. Pre-Flashpoint Kent kept tabs on his former villains to ensure they did not do as they did in his universe.
The New 52 Superman dies in the Rebirth story-line after expending all his energy in a fight to save innocents. His body is turned to ash. Pre-Flashpoint Superman does some soul-searching and decides to step in to replace the fallen hero.
In the meantime Mr. Mxyzptlk has kidnapped Jonathan Kent. Mxy is upset that Superman did not come to save him while he was imprisoned by who we assume to be Ozymandias/Dr. Manhattan. While rescuing Jonathan, Superman comes to the realization that he was split in two between the New 52 (red energy) and pre-“Flashpoint” (blue energy).
Jonathan is able to sense the red energy of New 52 Lois and Clark. He is able to merge the two (red & blue energies). The result is Lois and Clark being in existence with a unified history overwriting their individual lives.
We see the mysterious Mr.Oz watching the whole event. He seems surprised by what has happened saying “Love does conquer all”. Mr. Oz did hint at the beginning of Rebirth that Superman is at the center of the whole Rebirth story-line.