Evil Buu was clever, too. He didn't rush to fight the Shadow Dragons. Instead, he sensed the changes in Earth's power levels and discovered that one of the Shadow Dragons wasn't all that powerful. So he decided to go absorb that one first.
That Shadow Dragon was the Two-Star Dragon, the weakest of them all. His techniques were decent, but his fighting power wasn't much to look at. The moment they met, Buu absorbed him. After all, he wasn't very strong.
Then Buu went around absorbing powerful foes like he was taking on one boss after another, growing stronger before moving on to the next challenge. Whenever he couldn't beat a Shadow Dragon, he absorbed the survivors on Earth or the Z Fighters instead. By then, he had absorbed the Two-Star Dragon, the Seven-Star Dragon, the Six-Star Dragon, the Five-Star Dragon, as well as the Earthlings and the Z Fighters.
Now Buu wasn't sure what to do. He'd already absorbed everyone he could, and he was strong enough to beat the Three-Star Dragon. But the Three-Star Dragon was seriously obnoxious. He was supposed to be the Four-Star Dragon's brother, yet the two were nothing alike. That snake in the grass had gotten under Buu's skin several times.
Just as Buu was wondering what to do, he sensed two powerful fighters battling nearby. Without a word, he concealed his ki and went to watch. To his surprise, it was the One-Star Dragon fighting the Four-Star Dragon. The One-Star Dragon needed the other Shadow Dragons' Dragon Balls to become the Super One-Star Dragon, but he couldn't find any of them. The only one he'd found was the Four-Star Dragon, so he'd attacked him.
The Dragon Balls in this world had been enhanced far beyond their original versions. The original Dragon Balls could grant only two wishes, but these could grant three. The One-Star Dragon had been born from the Dragon Balls' increased power, so he was much stronger than his counterpart in the original story. The Four-Star Dragon was no match for him, even though he kept burning the One-Star Dragon.
In the One-Star Dragon's eyes, though, the Four-Star Dragon was doing nothing but struggling in vain. Before long, the Four-Star Dragon, who had been on the back foot the whole time, was knocked to the ground and couldn't get back up. The One-Star Dragon began taunting him.
Everyone knew villains died because they talked too much. But the One-Star Dragon didn't die—he just brought trouble on himself. The Four-Star Dragon was in no shape to fight back.
While the One-Star Dragon was distracted, Majin Buu quietly slipped into a crack between the rocks where the Four-Star Dragon lay.
In a flash, a chunk of Majin Buu's body split off and swallowed the Four-Star Dragon. The One-Star Dragon panicked. He'd spent ages searching for the Four-Star Dragon, and now he'd finally found him, only to lose him just like that. But Majin Buu had no intention of fighting the One-Star Dragon. While the One-Star Dragon was still standing there in shock, Majin Buu fled and concealed his ki. The One-Star Dragon couldn't believe someone else had absorbed the Four-Star Dragon. He'd thought he was the only one capable of absorbing a Shadow Dragon Ball.
By the time the One-Star Dragon snapped out of it, Majin Buu was nowhere to be found. Buu knew what he wanted to do next. Now that he'd absorbed the Four-Star Dragon, the Three-Star Dragon couldn't possibly beat him. No matter how much the Three-Star Dragon annoyed him, Buu had nothing to fear with such a huge gap in their strength. He planned to absorb the Three-Star Dragon, then see if he was strong enough to fight the One-Star Dragon. If he was, he'd absorb the One-Star Dragon, too.
But after Buu found the Three-Star Dragon and absorbed him, he didn't go looking for the One-Star Dragon. He knew it would take time to master all the power he'd absorbed. If he went after the One-Star Dragon right away, he definitely wouldn't be able to beat him.
Meanwhile, the One-Star Dragon searched every corner of Earth but couldn't find another Shadow Dragon. An idea crossed his mind. Could that pink guy have absorbed all the Shadow Dragons? It has to be. Otherwise, why can't I find any of the others? Wait. If he can absorb the other Shadow Dragons, that means he can absorb me, too.
The thought made the One-Star Dragon break out in a sweat. He knew it was true—he'd seen Majin Buu absorb the Four-Star Dragon with his own eyes. He had to find Buu as soon as possible. If Buu mastered all those powers, and the One-Star Dragon couldn't beat him, he'd be absorbed, too.
But Majin Buu didn't seem to be in any hurry. He kept hiding while the One-Star Dragon searched the whole planet for him. By then, very few people were still alive on Earth. Buu had absorbed the Z Fighters, too, and with no way to contact the God of Destruction's Temple, there was no one left to protect the planet.
Once Buu had absorbed most of the Earthlings and the Z Fighters, his next target was the One-Star Dragon.
When Majin Buu and the One-Star Dragon finally crossed paths, neither said a word. They immediately began to fight. Buu's fighting power was nowhere near the One-Star Dragon's, but there was no way the One-Star Dragon could defeat him. Unless the gap in their strength was enormous, Buu's terrifying regenerative cells made him impossible to kill.
So neither of them could kill the other. But that didn't mean Majin Buu couldn't absorb him.
At that moment, the system suddenly issued a mission.
A battle between Majin Buu and the One-Star Dragon has been detected on Earth. Host, please make a choice. Choice One: Have Majin Buu absorb the Super One-Star Dragon, then kill Majin Buu after he absorbs the Super One-Star Dragon. Reward: Perfect Super Saiyan 4 Choice Two: Have the One-Star Dragon evolve into the Super One-Star Dragon, then defeat him. Reward: Super Saiyan God Blue and Majin Buu Cells Choice Three: Do nothing. Reward: 1,000 System Coins Choice Four: Have the Z Fighters defeat them both. Reward: Indestructible Potara Earrings and Super Dragon Fist
Seeing these choices, Wei Dong's eyes lit up. Holy crap, this is my chance! How could I let it slip by?
He explained the situation to Son Goku and the others. They wanted to get back to Earth immediately, so they had no choice but to rely on Whis. But then Wei Dong remembered: right, his Instant Transmission worked just like Kibito's. He could go wherever he wanted. Before he'd even finished speaking, Wei Dong vanished, leaving Son Goku and Vegeta standing there in confusion.
"Hey, Vegeta, it looks like Wei Dong forgot about us."
Vegeta clenched his fists. "By the time we get there, Wei Dong will have wiped out Buu on Earth. Kakarot, can't you use Instant Transmission, too?"
"Uh, I can't sense anyone on Earth, so I can't teleport there."
Vegeta was speechless. In the end, he could only ask Whis to take them there.
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