At an unknown moment, Chen Tao prepared to set out alone.
Well, strictly speaking, he was not alone. Hidden within the alternate space of the Metal Spirit inside Chen Tao was Martha Wayne, who had seized Emperor Joker's Fifth-Dimensional Power.
After having Martha Wayne seize that power, Chen Tao had ordered Bane to grant her control over The Black. That was all for this very moment.
Simply put, the reason Prime Universe Thomas Wayne and Prime Universe Martha Wayne could appear and wander around in the current reality of the Over-Time Stream was purely because The Batman Who Laughs had ripped three branching timelines from the main timeline and pulled off an act of utter inversion.
He twisted the three branching timelines together, then overlaid them onto the main timeline, causing the history in which the Waynes were alive to overwrite the history in which they had died.
But as Chen Tao restored order, that overlay had effectively been erased.
Therefore, Martha Wayne should not have been alive. She should have died in Crime Alley.
If Martha Wayne remained alive because Chen Tao had previously given her Emperor Joker's Fifth-Dimensional Power, it would create a temporal paradox:
How could someone who had clearly died still be alive?
That would be presenting the Over-Time Stream with a problem. At that point, the Over-Time Stream would begin twitching and uncontrollably fabricate history, trying to patch the bug.
For example, it might fabricate a history in which Martha Wayne had never died but had instead changed her name to Alice, then followed a rabbit into the Fifth Dimension, or something equally nonsensical, to explain this distorted reality.
After all, the Over-Time Stream could even fabricate a history in which P Superman did nothing after entering the entire New 52. What could it possibly