Superman's Super Brain possessed not only super intelligence, but super memory as well. Although he did not normally use it, it was actually a passive ability. Superman could remember everything he had ever seen in perfect detail.
He would not notice anything unusual when he was not accessing that part of his memory, but whenever he wanted to recall something, he could remember every detail of everything that had happened since the beginning of his memories.
When Overlord Superman focused on the possible abnormalities Batman might have displayed, certain scenes immediately came back to him.
Batman had not started acting strangely only recently.
Overlord Superman's memories kept tracing backward until they stopped at a particularly significant moment: the night they had finally completed Earth's public security system and held a victory celebration.
The party and revelry were as usual, as was Batman's silence. Yet, unusually, he had not left early. Instead, he stood in a corner of the dance floor, quietly watching it all.
Overlord Superman could tell that he was happy. With his far-superior powers of observation, and his familiarity with Batman, he knew that although Batman had not smiled, this posture was the happiest expression he could possibly make.
So where had the turning point occurred?
Overlord Superman remembered that he had drunk some alcohol that night and, for once, allowed himself to get a little tipsy. He had slung an arm around Batman's shoulders, and the two of them had gone to the rooftop to enjoy the breeze.
He had gestured grandly and declared that he would bring such peace to every universe. From then on, people would no longer be troubled by criminals and would surely live orderly, happy lives.
And then, what had Batman said? Overlord Superman pushed through the haze of alcohol-induced illusions and