Superman (in his weakened condition from kryptonite) punches out mind-controlled Batman. He then takes out mind-controlled Alfred with a coffee mug.
Issue 5 qualifies. Superman has just been blindsided by Bizarro, who tackled the Man of Steel into the middle of the street so Solomon Grundy could help beat him down. Then Metallo shows up and begins weakening Superman with his Kryptonite heart while the Parasite drains Superman's powers and begins to join in the beat down. All in all, Superman is helpless, wondering why none of the JLA are responding to his distress call, and finally cries out for help. Just then a lightning bolt flashes across the sky and all of the villains get an "oh shit" look on their faces as a red and gold blur comes down and proceeds to take them apart. Bizarro? Punched into orbit. Metallo? Kryptonite yanked out of his chest. Parasite? Had that Kryptonite jammed in his chest, and since he had stolen Superman's powers, was instantly defeated by it. Solomon Grundy? Beaten unconscious into a crater. In the space of a page, these four powerful villains are handily and decisively dealt with. The blur finally slows down enough to reveal who it is, offering a hand to help Superman up.
Captain Marvel: "It's okay Superman. I got your signal. It's going to be okay."
Brainiac teleports to his spaceship, tricking Zatanna (who was tracking and following him) into outer space and Superman manages to rescue her within the 7 seconds before she would have died.
Black Manta throws a punch at Aquaman while wearing electrified, spiked knuckles. Aquaman casually catches the punch and crushes his hand.
Aquaman: "I have evolved to withstand the crushing pressures of the bottom of the sea. What chance did you ever have against me?"
Hal Jordan vs Sinestro with tworings - his regular ring, and one of Sinestro's yellow rings with a chunk of blue Kryptonite.
How about the fight between Superman and Captain Marvel, when the latter is being mind-controlled? Okay, Superman is considered the greatest superhero in DC, but Captain Marvel is his equal, and even has a advantage due to his magical powers and doesn't have Superman's weaknesses. And yet, Superman manages to keep him occupied until Green Lantern can destroy the mini-robots inside Marvel.
The Joker spends the entire story running around on the sidelines, totally aware of what was going on, despite not being on either team. And then he takes down Scarecrow in a Dracula costume.