Previously

Boros: *mind* This World's Finest Combatants. I can sense Immense Fighting spirit in them.

Boros stood up and greeted the Intruders

Boros: Welcome Earthlings. I am impressed on how you defeated my Two Generals. For that, I will tell you my Name. I am the Dominator of The Universe, A Being with no known Equal, My name is Boros.

Rose: What do you want from us?!

Boros: What I want?

He started to walk down from his throne and approaches them.

Boros: There exists a Prophecy.

Genesis: Prophecy? What are you on about?

Boros: 30 years ago. I overheard a rumor that a Being in a Far, Far away planet exists. A Being so strong, even I struggle. I wanted to eliminate this Threat, For He or she is in my way for Universe Domination.

The 5 prepared for Battle.

Boros: I ravaged every Planet of dozens of Galaxies. Finding whoever is that Being. But now, You lot may even bring me down. Come, And give stimulation, That is why am Here!

Several Minutes later

It wasn't even a Fight, It was a Massacre. The 5 girls now lie Unconcious, Crippled, Or Injured and yet Boros seems to be holding back.

Rose tried to attack again. But Boros dashed towards her and Kicked her into a Pillar, Shattering it in the process.

Boros: What a Disappointing finish. I really thought you 5 can stop me. I guess my Worthy Opponent is not here.

When Boros was about to kill one of the girls, He was stopped by a Flying Blade. He deflected it and saw the person.

Boros: Another one? *mind* What an Outstanding energy Levels. Maybe this is the one.

???: You're fight is with me.

Boros: Before we fight. Let us exchange names. I am the dominator of the Universe, My name is Boros.

Y/n: I am this Star system's Greatest Protector. I am Y/n.

That one word hit the 5 girls. Eri and Nezuko were crying happily. Genesis and Pneuma were smiling, but unable to move. Rose was smiling, Knowing her husband is still Alive.

Eri/Nezuko: Dad!

Rose: Love!

And now. For the Story Finale of I am Reborn.

Boros: Y/n. You have immense Fighting spirit. Tell me, who sent you.

Y/n: Your Creator, Alice.

Boros: *small grunt. Mind* Alice. Only way the Woman will do this, is She took interest in him. Then he must be it. *out loud* Y/n, You're now my Opponent.

Y/n: I intend to. This Planet, This System, is under my protection. *pulls out Judgement* That will not change.

Boros: *takes his stance* Then A threat to the system is here. Come!

And the Final begins, a Battle of Gods, One that will determine the Universe's Fate.

Y/n dashes away at high speed, unfortunately, Boros' right on his tail and lands a rough blow from behind, knocking the Mighty Demi-God to the ground. But he gets back up and heals from the attack. The Dominator somersaults and charges at full force, fists burning with energy.

Boros: Don't walk away from me, Prophecy-Boy!

Y/m blocks the assault with one hand, despite being pushed back. He holds Boros by the arms before charging up his own power.

Y/m: Boros, you're in for a surprise!

And he strikes with a lightning-charged punch sending his blonde attacker flying back across the street. But Billy has only started, he charges in with a few slashes from Judgement, The Retribution kicked in and did alot of Damage to Boros. But This was far from over

In the sidelines, Genesis and Rose took their Last bit of strength to teleport them, Pneuma and the kids out of the Battlefield, Knowing they'll just get in the way.

Across the city skyline, Boros took hit by hit by the Sword until he successfully blocks it with a barrier of energy. Now he starts going on the attack, only to be blocked by Y/n.

Y/n: When in doubt, punch it out!

Boros only sighs and rolls his eyes at the lame one-liner. And quickly puts up his forearms in a defensive position as his opponent bombards in a hail of punches and slashes.

But the Sword was taking its toll on someone like Boros. The moment the sword was pulled back, Boros took the chance and did a Light speed attack. And ended up shattering Judgement.

Y/n threw away the Handle. He got out Purge and spawned a 2nd one, Dual wielding the electric Tridents.

Boros: You got skill for someone like you. You are exciting me to go further.

Y/n: You got strength to break a good Blade like that one. Here we go again.

I threw the tridents at him and he deflected them with his hands, I throwing more and more as the Electric current in them gets stronger.

Boros: You're making me bored. 

Y/n: Trident Eclipse

All of the surrounding tridents charged up and seeked out Boros, covering him in a massive electrical explosion.

He took a breathe and despawned my tridents. When suddenly, Boros came out, Grazed, and broke Purge.

Boros: I felt that.....just a little..

He tried summoning it again, but it didn't work. But He remembered what Notch said during training.

Flashback

Y/n was training with Notch, perfecting and honing his skill with the Trident and Legendary Sword.

Notch: Impressive. But do not let your guard down with Purge.

Past Y/n: What do you mean?

Notch: You may have nearly infinite of them. But if the Real one ever breaks, the rest comes with it.

He was surprised. He has to be careful now.

End of Flashback

Boros: Come on now. That can't be all you got.

Y/n: *mind* Fists it is.

Boros' Body glowed as he transformed. Going full power

Boros: Time to go full power. You excite me Human, Only you of your race have survived long enough for me to go full power.

Y/n: I guess it's an honor.

He took a stance, similar to her Daugther's Fighting style, Water stream Rock Smashing fist.

As they clash, Y/n continuously parries and redirecting Boros' attacks. The sheer intensity of their attacks made the Entire ship shake. They kept clashing endlessly, shattering Pillars, breaking the Sound Barrier, and Afterimages

Y/m then finally throws out a punch that takes Boros' arm off. He used the momentum of Boros' punch and redirected it.

Boros: Even though my Full power has been unleashed. You still fight on. You must have held back alot.

Y/n: Yup. I don't wanna damage Earth due to our power.

Boros: Very well. Let's take this outside then!!!

The fight continues to rage on as Boros knocks Saitama around the throne room and they eventually spiral out to the top of the ship.

On the ground

The family were debating if they should help him.

Rose: We have to help him!

Pneuma: We can't! Boros' too strong, We'll just be in his way.

???: *maniacal laughter* HAHAHAHAHAHA

They turned to see Centichiron and Geryuganshoop alive, but seems to be zombified or something.

Geryuganshoop: None can defeat lord Boros. Not even a God!

Pneuma charged at Centichiron. But before Centchiron attacks her,cshe jumped outta the way, As Eri came in, both of her Crafted Martial arts, nullifying its attacks.

The rest of the family battled Geryuganshoop, Who's intent on killing them is Tremendous.

Back to the MC and Boros

The two battled endlessly, Destroying Rooms in the Ship, Leaving tons of debris in their path. The two battled to the top of the ship.

Boros: Impressive. Out of All the Mortals, Beings, Gods, You alone have survived the longest!

Boros then starts to release destructive energy from within himself which damages the top of the ship, and the Skyscrapers infront of the beam.

The beam was so far, Y/n had to pull out two weapons to make a Shield. It was hard, but he managed to pull through. Unfortunately, His swords weren't so lucky. Devil Sword Dante and Yamato falls to the ground in pieces.

Boros: Two more broken.

He didn't respond, just pulled put another weapon, This was one was different, It was not The legendary sword, It was the Ark of the Cosmos.

A Mythical blade given by Alice. She said It is designed to kill Boros, But never tested against the being himself.

Boros: Looks like She gave you the blade. No matter!

He exploded energy into his severed arm and regenerated it.

Boros: Good as new.

The two fought more. Clashing fish to sword, Deflected attacks. And Ear shattering blows.

Boros struck Y/n so hard, He flew out of Earth and Into space. Boros followed him out and fought there.

The environment was something both are used to. From Fighting The universe, to Training in space, They can fight on equal footing.

More and more fighting later

Their battle is starting to shake the Universe. Planets exploding, Stars collapsing, and Black holes forming.

Boros was in his Strongest Form, Meteroic burst. It eclipses his speed and strength, and Y/n countered it with a Technique.

He uses the Powers stored in AotC and absored its powers, Tremendously increasing everything he needs in a fight.

Boros: FINALLY!!!! A REAL FIGHT!!!!

The two re-engaged in a fist fight, each clash causing ripples and tearing several Galaxies. Both were getting tired, Y/n was taking in more injuries, while Boros keeps on regenerating

He knew he has to end it here and now. He pulled out the Legendary sword, this time, it too was different, no longer Diamonds, now Netherite.

Boros sped behind him and locked him in a chokehold. Y/n tried to break free, but the injuries were taking a toll.

Boros: You fought well Mor-No. GOD. I have never experience this exhilitartion before. And it's gonna be the last.

Y/n: .......You're right. *smiles with a bleeding mouth* Our Last!

He stabbed himself with the Legendary Sword, catching Boros by surprise. They both spat out blood, but Y/n wasn't done. He pulled out the sword from boros, and Punched him so hard, He flew back to Earth.

With the sword still in his stomach, He knew he would waste time. So he rushed to Earth, intending to finish off Boros.

Boros puts himself back together and starts to initiate his final trump card, Collapsing Star Roaring Cannon, which he intends on wiping out the Entire Galaxy and all of its inhabitanta. Both yelled ontop of their lungs, shouting their final attack

Boros: COLLAPSING STAR!!! ROARING CANNON!!!

Y/n: WRATH OF GODS!!! ANNIHILATION!!!

Boros fired his Attack, hitting him directly, but That didn't stop him. He punched through the beam and hitting Boros in the chest, causing an Explosion that can be mistaken for a Collapsing Star.

All of the Gods used their magic to protect Earth from damage except them. The barrier shattered as the gods fell to their knees, breathless and weak due to using so much powers.

Aftermath

In the area. Boros was seen with a Burned body and Y/ n, still has the sword in his stomach, and missing legs.

Boros: Did I.....lose?

Y/n: It....was a tie....both of us will die...

Boros: The prophecy held true, It was a Battle of Gods.

Y/n: Heh. *chuckles then coughs blood*

Boros: My reign ends here. You are......the Strongest Being.....Y/n..

Boros disintegrated as his ashes was blown away. The family, who now found the Legless Y/n, rushed to him and Cried.

Y/n: This is it then.....The Bitter end

Rose: *in tears* You can't die....I lost you once...I can't lose you again!!

Eri: Dad! Please...Don't go...

He weakly pulls out the sword and gave it to them.

Y/n: Remember....Me

The Entire family hugged him and cried...

Y/n: Rose, Pneuma, Gabriel....The one who loved me where no one else didn't....know This, My love for you three will continue on..Till the end of time...

Y/n: And Eri...Nezuko...Thank for being there to cheer me up...I've always wanted daughters of my own..

Eri: D-dad!

Y/n: So long....girls...

Y/n body started to fade as Particles appear from his body. A few minutes later, All that's left was the Legendary Sword.

The End