*Yami Pov*
'So Goku is going to fight Jiren now for the first time. I kept all the nescassary fights in which is the love transformers, the 4 fusion giant, Jiren and Toppo and Kefla. I kept Cabba in for the sake of Vegeta. He would probably try to defeat me, which is impossible but still a bother. The people that I can fight right now without disturbing the plot would be Jiren when he is fighting Hit. Oh, wait. Since I replaced Frieza, I should at least do his job, so I'll send some energy to Goku. Though I'm not gonna fill in his roll of hugging Jiren all the way into the void. Well, time to watch.' I thought as I jump from rock to rock until I arrive in front of Goku and Jiren about to face off.
Goku immediately turns super saiyan blue, following the training I put for him to help him master Ultra Instinct faster. Unlike the anime adaptation, he is less loose and more dense if that is the correct phrase to word it. He doesn't underestimate his opponents as much as the original, which is good, but it still happens from time to time.
[Lets see how this fight goes down.] I said as I quietly observed the duo of fighters.
*3rd Pov*
Goku was the first to make a move as he immediately charges Jiren, sending a right punch. Jiren holds up his hands in an X shape as Goku's punch gets blocked. They start to dig through rocks, exchanging blows. Goku decides to step it up a peg as mid way during a kick, he turns Kaioken. Jiren tries to block which fails as the block gets overridden. The kick lands on Jiren's face which makes him crash into the rock. Without wasting anytime, Goku storms after Jiren planing to kick him up.
Jiren does a back flip in mid air, making the kick miss by an intch. That was all Jiren needed as he quickly grabbed the leg and threw it straight in the sky. He crouches as he jumps high, sending him to the same hight as Goku. Goku decides to use his full power, unleashing a Super Saiyan Blue 2 kaioken x10. It surprises Jiren as Goku grabs the punch coming at him. He tries to throw Jiren directly off the stage which fails as Jiren uses a little of his aura on his arm, making it increase in temperature. Goku still persists as he succeeds in throwing Jiren.
Jiren starts to manipulate his aura in such a way that it starts to become heavier and heavier. He lands at the edge of the arena which has cracks surrounding his feet from the gravity surrounding him.
[Lets go, Jiren!!!] says Goku as he starts to push himself to far, making blood start to leak outside his body. His moves started to become faint as all someone could see is slight blurs around Goku's arms. Jiren finds an opening and takes the opportunity to strike Goku on the chest with a powered up fist. It sends him to the opposite side of the area on top of some rocks.
[Tch, I guess ill have to use my strongest technique!!] said Goku as he deactivates his form and raises his arms.
[Strongest technique? Fine. Ill let you use it. Let's see what happens.] said Jiren calmly as he crosses his arms.
[Everyone!! Lend me you energy!!] said Goku as everyone besides Vegeta starts to give their energy to Goku. The massive amount of energy starts to gather on top of Goku's arms, forming a big blue ball with a white centre, measuring up to 50 meters in both hight and length.
[Lets see you take this, Jiren!!] said Goku as he throws the the giant amount of energy towards Jiren. Meanwhile, a certain Saiyan was snor- *cough cough*, drinking a can of infinite coke while watching the view.
Back to the story!!
Jiren holds out both of his hands right away as he brings out his own energy, trying to send the spirit bomb back to Goku. Without wasting anymore time, Goku goes into his strongest form and applies even more energy, making Jiren overwhelmed without adjusting to the current power. Jiren just barely adjusts to the good amount of power as the spirit bomb was a few centimetres away from his hands. Jiren's hands turn a faint red as the spirit bomb starts to charge back to Goku. Goku lets up for a seconds, making him lose his balance and fall into the spirit bomb, causing a massive energy explosion to appear in that area.
'Now then, will the butter fly effect make him dead? Or will plot armour keep him safe? By what I have seen, he has gotten stronger and the spirit bomb has also gotten stronger than in the original. Besides a slightly different attitude, everything should go the same as the anime. Welp, it doesn't matter. If he dies, I take over the tournament and win, get the dragon balls and revive him. If he lives, ill let him fight Jiren until he runs out of Ultra Instinct. If one doesn't work, Ill do the other.' Thought Yami as he checks the item in his jacket pocket. It was all safe with no damage at all.
A sudden light emerges through the ginormous hole as Jiren just looks down, followed by Toppo. Goku is seen in the middle of the light, slowly getting up. A silvery glow surrounds him as his black hair floats slightly with a small tint of white growing on the edges of his hair, barely noticeable.
Goku starts to walk towards Jiren slowly as he suddenly disappears and reappears in front of Jiren with a kick right next to his head which Jiren dodged. Goku does a flip as he tries to send a punch in which gets parried by Jiren's jab. Goku retreats back to the hole as Jiren chases him, moving the dust away with his hand and sending a kick in. Goku quickly speeds past Jiren, making a light scratch appear on Jiren's face.
[Impudent!! Surrender, Son Goku!!] screams Toppo as he sends his Justice flash towards Goku. Goku slowly turns around while walking towards Jiren, deflecting one of the many energy blasts. Jiren makes Toppo stand down as Goku continues with his barrage of attacks. The pair of fighters find themselves exchanging hundreds, if not thousands of blows in mid air, landing solid blows on each other.
The fight continues for a few more minutes with Goku's hair becoming a slightly more noticeable white. His eyes start to go back to normal as a slight look of frustration appear on his face. He knees Jiren in the stomach and brings his hands together which gets sent towards Jiren.
It forms an energy blast, sending Jiren towards the ground and bringing Goku towards the timer pillar. Goku lands on it as Jiren recovers. Using some of his strength on his legs, Goku propels through the air, putting all of his energy and strength into one last attack. The fist arrives at Jiren, spreading dust everywhere.
[You Saiyan's are truely a unique race, making me exert this much power.] said Jiren as the dust starts to settle.
[But.] he continues as now the scene is visible now. Goku in his base form has his fist held by Jiren's own fist.
[This heat of yours is your own limit.] said Jiren as he blast's Goku off with an energy blast.
Hit appears in front of Jiren, trying to land a strike which gets blocked by his other hand.
'Too bad, ill have to do Frieza's job of helping Goku. Oh well, not like there is anything more exciting here.' Thought Yami as he finishes snor- drinking his coke and teleports to Goku who is in the ground, stuck and out of energy.
[H-hey Yami, a little help here?] questioned Goku
[Hehe. Hehehehe, Hahahaha. Ive always hated you, and now we are in a blind spot where everyone cant see us. Its time for you to meet your end, Son Goku.] said Yami as he charges his energy in his index finger. He fires it through Goku who screams in 'pain'.
[Huh? Why did you give me energy? I thought you hated me. Is it because you cant fight me in this kind of state? Would this wound your pride?] questioned Goku
[Dummy, it was just a joke. With that energy, you should be good for now. Ill catch you later. By the way, congratulations on reaching Ultra Instinct sign.] said Yami as he immediately disappears the same way he appears.