Introduction
A Kai's offer
"Before you continue your fight, promise me this. Promise me that you won't waste the thousands of years I have given you" Old Kai said as he held his hand to Goku's chest, preparing to pass on his life to the Saiyan.
"I promise you that. I'll never let Buu Win" Goku replied. The sincerity in his voice was enough to confirm to the Old Kai that his decision was right. Closing his eyes, the Kai's body began to glow golden in a peaceful flame that then transferred from him, down his arm and into Goku who's eyes went wide as his vitality was reinforced and his halo disappeared.
With his life gone, the old kai sunk to his knees and slumped on the floor lifelessly. His final gambit of trust placed on the Saiyan Goku.
Goku's mind cleared as he snapped out of the memory. Sure enough, just as the old Kai had said, he had given Goku his life, and now Goku was over two thousand years old. His children, their children, and their children's children had long grown old and passed. He had spent many years watching over his descendants and the descendants of his friends, and had much training with Uub before he decided that there was more to the universe than just Earth.
Thus he had set off in a quest for experiences. Experiences that Earth could no longer provide.
Vegeta had long since decided to stop comparing himself to Goku, and had departed to find his own limits in the various realities of the multiverse. Now it was Goku's turn to depart all this time later.
As of now he had lived on MT Paozu in a home he had constructed with his own hands, and spent most of his time training, watching over the earth, or meditating in solitary contemplation.
Flying across the world, he spent some time watching over his long descendants before visiting the graves of his family that he had maintained for all these years.
Then he placed two fingers on his forehead and vanished from the Earth one last time.
When Goku popped back into reality, he was at the Grand Kai's palace at the throne room. As one of the only people important enough to enter and go unimpeded, Goku walked directly to the Grand Kai who had been sitting at his throne while reading a book. Some new age music was playing from a speaker he had installed on the side of his throne.
His large split beard hung beneath the book, his blue jeans, t-shirt, and his large fluffy hipster head of hair really clashed with what one might expect from the King of All the Kais.
Looking up from his book the greet the newcomer in his large opulent blue and golden throne room, he smiled and passed the book to one of his attendants who quickly took the book with a bow and scuttled off.
"Goku my friend, to what do I owe the honor?" The Grand Kai asked happily, springing off the throne with a heartiness not beholden of his age. He quickly jogged over to the Saiyan and greeted him with a big hug. He was a very unconventional ruler and had no shame in it. He was much like an old man who yearned to relive the joys of his youth again.
Goku hugged the old man back before the two broke apart and Goku got straight to the point.
"Well Grand Kai, I think I'm getting old" Goku said with a small laugh.
"Nonsense my friend, you're still quite young. Give it a few hundred thousand years, and then you can say that to me" The Grand kai replied with a laugh of his own before becoming serious.
"I think I know just what you need" He said, giving Goku a knowing look.
"Oh, Great!" Goku enthusiastically responded. He trusted the old man in things like this.
"You've been living on that small planet Earth for most of your life, and well, things just aren't what they used to be right? No tyrants ruling the universe. No ancient beings to fight. I can see it in your eyes, you've been looking for excitement. Something new right?" The Grand Kai asked walking with Goku out of the throne room followed by a large escort of powerful guards.
Raising his hand as they went out into a massive garden full of all sorts of prismatic flowers and plants. Various birds and large colorful creatures flew through and fro in the garden ignoring the promenade completely.
As they walked, the Kai continued to speak, and Goku, who had quite mellowed out over the past thousand years listened closely.
"You're not looking for a fight right? If you wanted that, you would have gone to hell and fought one of the denizens there. No, you want to feel what you felt in the first fifty years of your life, Right?" The Kai asked, reaching out his right hand. Within seconds, an attendant approached and gave him a small box.
"You're right. I've been looking for that excitement more and more these years. What should I do?" Goku asked, wondering where the Kai was going with this.
Opening the box, The Kai took out a small golden badge and handed it to Goku with some words.
"Take a vacation. Not just that, allow yourself to let it all go for a few hundred years" The Kai said, placing the badge in his hand.
"This badge will show that you have my blessing to any Kais or their employees. Think of it as an endorsement" The Grand Kai casually said before changing the subject.
"I think I know of a place where you can find just what you want. And more" He smiled, expecting an answer from the Saiyan.
"Where's that?" Goku asked, curious as to where the Kai was referring to.
"Remnant" The Kai responded with a grin, much like one would have after revealing important information.
"Remnant?" Goku questioned. He had never heard of this world before.
"Yes, its Earth in a different timeline, and I think you would do quite well there in finding the experiences you are looking for" The Kai responded with conviction.
"Great, how do I get there?" Goku asked.
"I'll send you there. At any time if you want to come back, just say these words".
"'Grand Kai, I'm done' are the words, but I doubt I'll be hearing them any time soon" the Kai said before snapping his fingers, and with that, Goku was gone.
AN: There is no super and GT in this story.