Spoilers ahead for this week's Action Comics #991.
This week's Action Comics #991 confirms that Mr. Oz really is Jor-El, and his ability to withstand Kryptonite are linked to his last-second rescue from an exploding Krypton.
The issue, by Dan Jurgens and Viktor Bogdanovic, continues the "Oz Effect" storyline that's been revealing the history and nature of the mysterious Mr. Oz. In previous issues, Mr. Oz told Superman and his family that he was actually Jor-El, the biological father of Superman (Kal-El). He claimed to be ripped from the surface of Krypton at the last second, imprisoned by an all-powerful entity, and forced to witness the worst of humanity's history.
Now his mission is to expose how hopeless humans are to his son and rescue his family from the impending threat of the unseen powerful character who imprisoned him.
In fact, readers get to see a bit of the powerful character's handiwork at the end of the issue - presumedly the work of Dr. Manhattan, who will be fighting Superman and friends in the upcoming mini-series Doomsday Clock.
Let's take a look at how the issue answered a few questions about Mr. Oz, resolved the "Oz Effect" storyline, and set things up for the future.
Is it really Jor-El?
The issue starts with Superman in disbelief that his Kryptonian father could really become Mr. Oz and do all the nasty stuff that he's been doing on Earth.
But - sorry to skip to the end a bit here - he really is Jor-El.
Jonathan wants his dad to give granddad a chance, and Lois is confused by what the heck is going on, so amongst the noise, Oz decides to explain himself.
He strikes the end of his staff into the ground and causes himself and Superman to be transported to his prison.
Actually, Oz says it's where he was imprisoned at first. But then it became his home. And, as we already knew, it exists outside of space and time.
Oz uses his staff again, this time the bladed top, to direct a blast of energy at Superman. He decides that he's done trying to convince his son to come with him. He is going to force him.
Answers to Questions
Question: Superman asks Oz, why did you masquerade as Oz instead of just talking to your family and telling them to leave Earth?
Answer: "Earth is sick," Oz says. "You need to see that for yourself, and Mr. Oz was the vehicle that allowed it to happen."
Question: Superman discovers the room where Mxyzptlk was imprisoned. Superman asks Oz, "you were his jailer?"
Answer: Oz says he did it to save his son.
Question: Oz uses his eye to send an energy blast toward his son. But it's not the normal Kryptonian heat vision. It's Kryptonite of some kind. Superman asks, how?
Answer: Oz had Krytonite lodged into his body when Krypton exploded (a split-second before he was transported away). "Rather than let it kill me, as it should have, I've been evolved to control it," he says.
Question: Superman sees that Doomsday was imprisoned in Oz's home. "But I sent him to the Phantom Zone," Superman says.
Answer: "I'm the one who discovered the Phantom Zone," Oz says defiantly. "Intercepting the projector beam to bring him here was simplicity itself." Oz says he feared that someone would find Doomsday and use him against his son.
Question: Why is Oz in such a hurry to get Superman and his family off Earth?
Answer: "I don't like doing this, but I know what's coming," Oz says. "It's so much bigger, so much more powerful than you."
Question: What's up with Oz's staff? Superman grabs Oz's staff and breaks it in half. "SNAPPT."
Answer: Superman says, "The energy surrounding this staff is toxic. … Were you controlling it, or was it controlling you?" Oz explains that the Krytponite was lodged in his skull after the explosion, and the staff eased his pain. "It made me …. he made me … I never meant to hurt anyone," Oz says.
Oz says he's sick. Superman says he'll try to find Jor-El some help. But Oz says Superman should stay back, or else he'll become affected too.
Jor-El apologizes. "This sickness," he says. "What it did to me … everything I experienced … I'm the one who's sorry, Kal."
Superman promises that he won't let his father die.
But Jor-El yells, "No! He's coming! I can feel it!"
He tells his son to find Lois and Jon, then fight for them and save them.
A swirling portal opens up and Oz says "he's taking me!"
His last words are, "I love you, Kal. I always have and I always will."
Superman yells to the swirling blue mass that now surrounds him, "What do you want from me?"
Nobody answers in this issue. (But, we assume, he'll get that answer in Doomsday Clock.)
Superman is transported back to the Fortress of Solitude. He wonders to himself if his father's predictions for the future are true. After all, this entity was powerful enough to manipulate Jor-El. Could he be powerful enough to defeat all of Earth?
He flies back to Metropolis, to the rooftop where Jon and Lois are waiting. Jon want to know where granddad is. Superman explains that he was taken somewhere, but he promises to find him.
Then he ponders what would have happened if he had arrived on Earth and been treated the way Jor-El had. "Would I see things the same way? Would I think Earth is a world without hope?"
Superman listens to the desperate voices around him - mentions of oppression, assault, racial conflict, limits on freedom of speech and more. He realizes people are losing hope.
He flies away, saying he has to get "back to work."
The story is set to continue November 22 in Action Comics #992, titled "After Effects."