"Whoaa! So this is the moon Ganymede! Awesome!" Goku jumped around excitedly in the low-gravity environment. "Guess asking dear Shenron for ability to breathe in space isn't a bad idea after all! I can go around exploring other planets on my o... wait, what's that?" As Goku leaped over a mountain, he saw a point of bright blue colours among the brown barren land. It seems like a man, sitting on the ground.
"Yo, Mr. Alien!" Goku walked up him. Superman, fully donned in his usual red and blue suit, saving his red underwear for some reason unknown to Goku. After he got interrupted from his deep thoughts alone, he turned around somewhat surprised. "A human, in space? Who are you?" "Are you kidding me, Mr Alien? We fought before!" Superman got more confused, seemingly with no recollection of Goku. "How did you get here?"
"That's not important, fight me!" Goku said as he swings his fist into Superman before Superman could stop him. Superman, who perceived it in semi-slow motion, was not amused. He caught Goku's fist with one hand, and then attempted to return the favour. Goku jumps back, threw up his forearms as Superman rushed to punching Goku. Goku was keeping up with him comfortably, before finally outclassing Superman with his superior martial arts skills. "You're fast, but not fast enough." Goku said as he thrashed Superman into the air. Superman chocked, amazed that there is a lifeform out here that is this strong.
"That's all you've got?" Goku said in a somewhat disappointing tone as he waits for his opponent to recover. "No, all this while I've been suppressing, you have released it!" The Man of Steel held his core and yelled in pain, as a white light leaked from his body. "Run, before I come with the strength of a God!" Goku smirked, "I've already battled a God before."
"Kaio-ken." Bissh! A red aura awakend around Goku as the God of Strength yelled indefinitely and moves in for heavier attacks. Goku, now tens of times faster than before, was able to dodge the attacks easily. "If you don't remember me, I will help you." Goku punched Superman in the face, then kicked him in the head. The bloodlusted Superman seems to be taking damage, but he ignores it, grabs Goku's leg while he was momentarily startled, and tossed him to the other end. Goku quickly maintained his balance. While the momentum was still pushing him across the ground, he took the chance and charges a Kamehameha at Superman. The kamehameha wave moved across the moon while it gravitated towards Superman and engulfed him, causing him to slowly losing his consciousness...
"Wake up Kal." Superman, who seemed to be in a white void, opens his eyes, dumbfounded. "Where am I? Wait, you are..." "Yes," the man replied, "I am you, or rather, your predecessor." Standing in front of him is none other than the usual Superman that we are all familiar with. "But how, you ask? Well, the cosmology of the world is... confused. It seems like multiverses are colliding. Characters from other worlds seems to be able to cross over. And you, Kal, are able to access the previous version of yourself." He said as he turns around and extends his hand. "Come, its time you take a break, Kal."
A blinding flash illuminated the surroundings. Goku, now powered down, shielded his eyes in bewilderment. Superman, with his less-brightly coloured costume, walks out as the light dims. "Long time no see, Son Goku. Are you stronger now?" "Heh, see for yourself, Mr. Alien." "Take your senzu bean. You and I are going to have a fair match." "Nah, I don't think I need one of those yet." Goku smirked, as he transforms into Super Saiyan! "Let's do this."
As the two collided again and again, the collateral damage from their collision destroys entire mountain ranges. Superman gradually gets faster and faster, and punches harder and harder with every collision. Goku, who was testing Superman's power, transforms into Super Saiyan 2 mid-battle as Superman is gaining on him. The Man of Steel barely holds his own with Goku suddenly gaining twice his power from before.
After a long battle, Goku finally jumped out. "Alright, that's enough." Bam! He turned into Super Saiyan 3, as his golden hair grows longer to his waist. Goku remarked, "This form won't be advantageous in the long run, I better finish this fight quick." "That won't be happening." Superman's said as his eyes darkened under the shadow. "You are not the only one who got stronger, Son Goku." Then, Superman released his golden form.
Goku narrowed his eyes and move into his fighting stance. "I have been in the Sun for thousands of years, longer than most people could imagine." Superman said as he paced himself towards Goku. "This time, I have surpassed my limits, just as you have been." Faster than light, Superman appeared above Goku and shadows him before he could barely react, even though Goku was fully in alert. While in the air, he throws a punch down onto Goku. Goku got a scrape from barely dodging it, but the punch moved onto the ground. With such an immense force, the tremors broke out an Earthquake larger than Earth had ever experienced, and decimated the celestial body. With the gravity completely disrupted, the thin atmosphere released itself into the outer space. Goku quickly moved away, dodging the fragments of the continents that was sent flying everywhere. "How long will your golden form last against mine?" With no ground to stand on now, they flew facing each other in the seemingly empty void. "Yes, Super Saiyan 3 can't last long enough. But I have something else that can. Haaaaaaa...." As Goku powers up, a fiery aura suddenly emerges around his body. He became a Super Saiyan God.
Superman watched in dismay as he learned that Goku has surpassed his limits again without his knowledge. The two rushed towards each other as they are about to break out a fight of the century.
Super Saiyan God Goku, or Superman Prime One Million. Which of the gods will emerge victorious? Find out on the next episode of Dragon Ball Z.