Wasn't this one some sort of god or something?
it was the DC 1 million superman prime. essentially a superman that had crossed the ends of the universe, trained under the DC universe God, then came back and meditated in the center of the sun for centuries. Anecdotally he was laughably overpowered but doesn't have a whole lot of feats on panel.
This does give me an opportunity to address this comment though, since i think i was sleeping or not paying attention when it came up.
I am wondering if the upcoming match will address the one major weakness of Goku in a match vs Superman:
the Z Fighters' invulnerability is transient. Without spoiling too much, let me just say that the latest movie confirms that a character at Zarbon-level from Namek saga can in fact kill an individual above the level of a Super Saiyan God with a single shot if that individual is caught unaware. Z fighter invulnerability comes from the raising of one's ki level in an instant, something which was only briefly mentioned waaaaaay back when Goku first showed up on Namek. Superman's invulnerability is a nonstop thing.
In terms of sheer destructive output though, the current incarnation of Superman has nothing on Goku. The Z fighters have been planet busters for a while.
modern incarnations of superman can bust moons and planets with physical strikes alone. We don't know exactly how much stored energy he can channel into heat vision, but I've never seen a practical limit to how much he can store- the best feat I've seen that even attempts to give a number is superman using his body as a solar battery to absorb the "anti-sunlight" powering mageddon- explicitly called out as being enough energy to vaporize "half a galaxy". He absorbs this on top of his default power level with only momentary ill effect- implying a fully charged (say, sundipped) superman is going to be well past this.
But let's address the Z fighters being "planet busters." I'll accept on face value that any of the saiyans should be able to muster a ki blast strong enough to break the planet apart. but how impressive is this when stacking it up next to how durable superman is? (and again, consider that superman's durability is a passive skill that requires no concentration and is always at max).
here we have superman tanking a supernova:
caught in the middle of the impact of new genesis and apokolips- both planets are 60x the size of earth:
We know that a yellow sun gives superman his powers and will charge him if he goes near one. Here we have superman flying straight through Krypton's massive RED sun and crashing into the planet sized Mogo. Depowered, but unscathed.
Here we have superman tanking an explosion rated at
fifty times the size of Kepler's supernova- essentially 50 supernovas, and he was at the core. This one didn't even knock him out
and his powers were rapidly depleting beforehand.
There's no one in DBZ that has anywhere close to this kind of power output, and none of these things was able to hurt superman either. (The supernova ko'ed him temporarily, with no other physical damage) There's no one with a power output sufficient enough to actually permanently injure superman anywhere in that show.