Dragon Ball: Goku Rebirth - 69 The Universe Source
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69 The Universe Source

"Well tough Gohan, who was it again that wanted to go out with me!" With no way to get out of the attack, Gohan simply laid there while enjoying the feelings of the marshmallows on his head.

....

6 Months Later:

[Task 8: Unknown Enemies Have Arrived!]

[Mission introduction: Protect your Planet from the impending doom it is about to face. ]

[Task requirements: Defeat the uninvited guests from a Galaxy far, far, away! ]

[Task Reward: ??]

Goku had just gotten a "*Ding" in his mind with this saying that the task was completed however he didn't know what reward he had acquired, and was immediately excited about the item or ability, etc he would get.

[Host has successfully acquired the "Spark Of Divinity 2/2"]

When Goku heard this echo in his mind he became agitated as clearly he had gotten this reward before meaning it's not of use to him, but then he saw "2/2" this meant that he got the incomplete spark at the start.

And instantly in his inventory the two sparks fused together and formed the "Essence Of Divinity", and instantly the System asked, [Host has acquired the "Essence Of Divinity" does Host wish to fuse this into his Base Form?]

When Goku heard this echo in his mind he thought 'Yes' and instantly his body began glowing in a red and gold light causing the surroundings to disintegrate due to his immense power.

And instantly half of his house was vaporised

Causing everyone to arrive near him however they didn't get too close as the mere energy released off of Goku was immense and Gohan, Trunks, Majuub and Goten couldn't feel Goku's Qi anymore.

Making them ponder exactly why he was vaporising everything around him yet they felt no Qi. And inside this gold-red aura Goku was clenching his fists as the "Essence Of Divinity" was merging with his body and soul causing Goku immense pain as the merging was changing every meridian, bone and muscle of Goku's as they kept on breaking and growing back even more dense and stronger.

And after a while the aura grew so big that Goku's pores opened up and blood started to fall from his body as his veins popped causing red viscous liquid to pour down his body as he howled in pain, "RAAARGH, AAAARGH!"

....

And finally it ended his body had merged properly with the Divine Essence, causing his body to become much more lean and the biggest change was that his hair turned blood red, after this his "Three Realms Regeneration" activated instantly healing all the damage that occurred to his body and instantly his body was healed however his mind was still as he lost consciousness.

And unbeknownst to Goku was that the one who reincarnated him had appeared once again, the dark Purple haired Saiyan Hakais.h.i.+n who had taken a liking to Goku had appeared again as he witnessed him ascending into the peak of the Saiyan race, as Goku became the Alpha Saiyan.

Soon after while Goku was still unconscious, the Hakais.h.i.+n told his attendant to freeze time as it was now time to defeat the enemy that had been plaguing him from the start Demigra!

Demigra wanted to destroy the Time Vault and remake history and the universe as he sees fit. And so to combat this Omega the Hakais.h.i.+n Of Time decided he needed help in delaying Demigra's plan, that's why he had created so many alternative universes and timelines in hope that he could destroy Demigra but not meddle with the Universe Source.

The Universe Source was the main cannon as you call it, and if meddled with every timeline could be at stake, this was what Demigra wanted he wanted to create his own multiverse and timeline.

And Omega was the only one capable of stopping this but he needed Goku or at least a part of Goku as Goku was the key to destroying Demigra who was an anomaly.