Many years ago, I caught an episode of an animated Superman show done in the iconic Bruce Timm style of Batman: The Animated Series. I've tried to figure out if the episode was from a Justice League series, Superman's own title, or something else I don't remember.
Some details about the show follow, but I could be conflating more than one show. Or episodes of the same show, for that matter. All manner of apologies if so.
Superman is working with a team of other superheroes to stop... some plot, and I didn't see the whole thing to know what it was.
A missile - an ICBM, perhaps? - is launched, and the heroes have to stop it
One character I didn't know (I think I remember wings and a red suit?) was pushing the missile and was in physical contact with it
At some point...
the bomb detonates, vaporizing whoever the character was on the missile
After viewing video footage of the event, it turns out...
Superman detonated the missile with his heat vision, deliberately murdering the other character.
Wonder Woman (I believe) and some others go to Batman for help. When Batman sees the video footage, he...
gets a bit of kryptonite he's storing in the Batcave; when asked why he had it, he says, "He's gone rogue before," or something to that effect (not an exact quote)
In the end, it turned out...
Supes had been suffocated to unconsciousness by an alien creature similar to a sea star. It took over his body and was using it to protect itself and position itself to take over the Earth.
And it all started when...
Superman had to rescue a spaceship full of weird creatures taken by someone for their own amusement; a zoo, of sorts, basically. Some of the aliens in the ship, contained in simulated environments for each of them, were sapient...like the sea star. Superman couldn't return them home because whoever owned the ship was...killed, maybe? during the fight with Supes, and he didn't know where they'd all come from, let alone how to get them back to wherever they came from. So he kept the ship under his Fortress of Solitude.
It was at least a two-part episode of the show.
That's about all I can recall, and the details, again, could be off, or at least a conflation of other shows/episodes of the same show. But my Google-Fu fails me whenever I try to find it online.