After everyone on King Kai's Planet had been revived, Son Goku used Instant Transmission to take them straight back to Bulma's House in West City on Earth.
Seeing everyone alive again, Bulma wept with joy. In a rare show of tenderness, Vegeta told her, "Thank you for everything you've done all these years."
Bulma smiled through her tears and said to Vegeta, "So you do know how to care about someone."
Vegeta's face turned bright red. He snorted and went straight into the house.
Seeing this, Bulma led everyone else inside as well.
With Son Goku's wish fulfilled, Earth regained the prosperity it had enjoyed before the Androids appeared.
At Kami's Lookout, once his wish had been fulfilled, Son Goku took Trunks to say goodbye to Kami and Mr. Popo, then used Instant Transmission to return to Bulma's House.
Kami asked Dende to stay behind, saying they had something important to discuss.
Son Goku knew what Kami meant and left them to it.
Son Goku and Trunks appeared before everyone at Bulma's House in a flash.
Bulma said to Son Goku, "Thank you so much, Goku from the other world."
Son Goku said, "You're welcome. Now that everyone's been revived, it's time I returned to my own timeline."
Hearing this, Trunks asked, "Uncle Goku, won't you stay a few more days?"
Son Goku said, "No, Trunks. Make sure you keep training hard."
Then he said to Bulma, "Bulma, you should know how to build Gravity Rooms by now. You can build a few to help everyone train. High gravity is a big help in increasing strength, especially for us Saiyans."
Bulma said, "I see. All right, Goku, I understand."
Son Goku continued, "Bulma, could you write down your knowledge, insights, and experience with building the Time Machine in a book for me? I plan to give it to Bulma when I get back and ask her to help build a Time Machine."
Bulma replied, "Of course. I wrote it all down a long time ago, just in case something happened."
Then she turned and went into the house to find the material.
Son Goku then said to the Son Goku of this world, "Kakarot, you can teach everyone the Kaioken. At high multipliers, it can boost your strength even more than becoming a Super Saiyan."
Son Goku nodded. "Got it, Kakarot from the other world."
Just then, Bulma came over to Son Goku with a thick book and said, "Goku, this contains all my knowledge, insights, and experience with building the Time Machine."
Son Goku took the book and said, "Thank you, Bulma."
Bulma said, "You're welcome, Goku."
Then Trunks climbed into the Time Machine, set the timeline coordinates and destination time, and said to Son Goku, "Uncle Goku, all the settings are ready. We can leave now."
Son Goku nodded, climbed into the Time Machine, and waved goodbye to everyone.
A moment later, a white light flashed, and the Time Machine vanished from the Future Timeline with Son Goku and Trunks aboard.
In the past timeline, Bulma was sunbathing in the courtyard when a machine suddenly appeared in the sky.
Once the Time Machine landed, Son Goku jumped out, flashed over to Bulma, and swept her into his arms. "Bulma, did you miss me?"
Blushing, Bulma said, "Goku, put me down! Someone's watching."
Only then did Son Goku set her down. He pointed at Trunks and introduced him to Bulma. "This young man is Trunks from the future world."
Trunks said shyly, "Hello, Ms. Bulma."
Bulma smiled. "Hello, Trunks."
Just then, everyone came out of the Gravity Rooms and gathered around the three of them.
Piccolo asked, "Goku, did your trip through time go smoothly?"
Son Goku said, "Everything went smoothly. The Androids have all been destroyed, and I revived all your future selves too."
Piccolo said, "That's good. How strong were the Androids in the future world?"
Son Goku said, "They were a little weaker than Vegeta is now."
"Oh, I see," Piccolo said.
Vegeta snapped angrily, "Piccolo, what's that supposed to mean? Are you looking down on me?"
Piccolo snorted but said nothing.
Son Goku said, "Stop arguing. Next, I'll train you all and improve your strength so you can face any powerful enemies that might appear in the future."
No one spoke. Son Goku called to Trunks, "Trunks, show them how strong you've become after training with me. Let them see what you're capable of."
Trunks said, "No problem."
Then, with a loud shout, he transformed straight into a full-power Super Saiyan 2.
Everyone was stunned when they sensed Trunks's strength.
Piccolo asked Son Goku, "Goku, how did you train Trunks? This kid is practically a different person."
Vegeta added, "It's only been a few days, Kakarot, and you've already trained this kid into a Super Saiyan 2."
Son Goku said, "You know about the Hyperbolic Time Chamber, right? Trunks and I spent two years in there."
Piccolo said, "That explains it."
Son Goku said, "Each of you is different, so I'll put together individual training plans for you. Follow them, and you'll all grow stronger."
Everyone nodded.
Son Goku nodded in return, then said to Bulma, "Bulma, help me get some food ready. Let's treat Trunks to a meal."
Bulma nodded and was about to leave when Son Goku handed her the book he was holding. "Future Bulma gave this to me for you. It contains information about the Time Machine. Take it."
Delighted, Bulma said, "Wonderful! With this information, I can avoid a lot of wrong turns and build a Time Machine very soon."
Son Goku nodded. He had wanted Bulma to build a Time Machine as soon as possible so he could travel through time, visit different parallel worlds, and grow stronger.
After Bulma left, Son Goku took Trunks on a tour of several Gravity Rooms.
Only after seeing the Gravity Rooms did Trunks understand why everyone was so much stronger than their counterparts in his world at the same point in time.
Afterward, Son Goku touched a finger to Trunks's forehead and passed on the method for training in the Kaioken.
He told Trunks, "Combining the Kaioken with a Gravity Room is a huge help in increasing your strength. Trunks, make sure you take it seriously."
Trunks said, "I understand, Uncle Goku."
Once Bulma had prepared the meal, Son Goku and everyone else began wolfing it down.
The Saiyans tore through the food like starving men. Son Goku thought, Chi-Chi and Bulma are probably the only people in the world who could afford to feed this many Saiyans.
After everyone had eaten their fill, Trunks climbed into the Time Machine. As everyone waved goodbye, he started it up and returned to the future world.
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