Vegeta, keeping tabs on the boys while he was training, froze in shock when he felt the impossibly high surge of energy. Immediately he turned the gravity enhancer down to normal and ran out of the training room, taking flight when he got outdoors. As he headed toward them, he could sense one boy's energy dwindling. The other was fading rapidly. Sensing the pressing need to be swift, he disappeared. When he felt the boys below him, he stopped. Registering a sudden presence on his left, he turned to see Goku materialize beside him.

"Let's go," Goku said, starting to head down to the limp forms below.

"No!" hissed Vegeta, grabbling his arm. "Kacarrot, you fool, this could be a trap! What if something attacked them?" So the two Saiyans were forced to waste a minute of precious time, searching the surrounding area to ensure it was safe. Then they rushed to their boys. Trunks was sprawled on the ground facedown, his right arm jutting out from the shoulder unnaturally. Goten lay next to him, ghostly pale. Goku and Vegeta quickly checked their vital signs. The weak pulse in the neck of each child signified that they were both alive, Goten barely so.

"Get Dende," Vegeta said tersely. Goku didn't need telling twice. He placed his two first fingers against his forehead and was gone, traveling by Instant Transmission to the Lookout. He was back before Vegeta could blink.

"What—where—?" Dende stammered, disoriented from the unexpected journey. Goku led him over to the fallen boys.

"Please, Dende," he begged urgently, "help them!"

The Namekian's eyes widened in shock, but he didn't ask questions. He knelt next to Goten and ran his hands gently over the boy's body. "It's all right now, Goten." He spoke calmly as usual, with the wisdom befitting a Guardian of Earth. "I'll heal you." Goku's fists were clenched; his fear was so great Vegeta could practically smell it. Dende held his hands over Goten. His antennae began to glow a soft gold. The healing light spread to his hands and flowed into Goten. After a few moments the boy stirred. He sat up as Dende's healing light faded away.

"Goten!" Goku exclaimed in relief. Goten was taken by surprise as Goku's arms wrapped crushingly around him.

"Ugh—Dad? Whoa, what happened?" He blinked over his father's shoulder. "Why is Dende here?" Neither the Namekian nor Vegeta was paying much attention to them. Dende had now turned his healing power on Trunks.

"You'll be good as new, Trunks," he promised the boy. "Just hold on." The light glowed around him briefly and was gone. Trunks pushed himself up.

"Huh? Hey!" he cried as he came to his senses. Seeing all the people around him, he scratched his head and asked, "Why is Dende here?"

The Earth's Guardian laughed. "Yep, they're back to normal," he pronounced.

"Thank you, Dende," said Goku fervently.

"Wait, 'normal'?" repeated Goten, still confused. "What do you mean? What happened?"

"That's what I'd like to know!" yelled Vegeta. He glared at his son. "Were you two playing hide-and-go-seek, or trying to kill each other?"

"Well, I used my Kamehameha, but then…" Goten put his finger to his mouth. "I don't remember."

"You don't remember?" Goku repeated his son's words with disbelief.

"Well, isn't that convenient," Vegeta observed dryly. "Our sons are half dead on the ground, but neither of them knows why or how." He pointed to his son. "Get back home. Right now! If you're going to kill yourself, at least have the decency to do it under your own roof."

Trunks gulped and powered up. "Right, Dad." He took off in a jiffy.

"Um, I'll go home, too," said Goten nervously, and hurried after Trunks. Goku watched them go.

"They don't remember," he said again as though saying it would help him understand it.

"It's strange," mused Dende. "They had terrible injuries. Trunks's arm was twisted somehow, and Goten broke his neck." Goku sucked in his breath when he heard that. "But those two never get hurt…" Dende went on. "And you mean to tell me that all this happened because they were fighting together?" He folded his arms and shook his head, looking like Piccolo. "It doesn't make sense."

"Tell me about it." The deep voice was followed by its owner as Piccolo himself swooped down to them feet first.

"Piccolo!" Goku greeted his old friend.

"And that's not the only thing that doesn't make sense around here," the tall Namekian continued.

Vegeta blinked. "What do you mean?"

"C'mon, Vegeta, you could feel the energy as well as I could," Piccolo pointed out. "You know that your sons couldn't put out a power level of that magnitude. I know they're powerful," he conceded, "but two Saiyan boys wouldn't have a power that high. Not unless they were pushed to their limits and beyond. And from what they've told you, it appears they were just playing."

"So what are you saying?" Dende asked with wide eyes.

Piccolo looked down. "I've been having…I don't know. Dreams, or visions, I guess."

"But you said you couldn't tell anything for sure!" Goku reminded him.

"Oh, so you know about this, Kacarrot?" Vegeta glared up at his rival. "And just when were you planning on telling the rest of us, I wonder?"

Goku waved his hands in an apology. His sheepish smile was that of a young boy's. "Sorry, I just—we didn't want to worry anyone, that's all."

"It's a little late for that, I think," Vegeta pointed out, rolling his eyes. He rounded on Piccolo. "Stop stalling and tell us, Namekian! What did you see?" Piccolo kept his eyes on the ground and didn't answer for a long moment. Then he breathed deeply and replied,

"Earth was under attack."

"By whom?" Vegeta pressed him.

Piccolo shook his head, his eyes unusually far away. "I couldn't see anyone or anything definite. It was more of a…feeling. Earth was being attacked. And our friends were in danger. The aggressor took us all by surprise."

"Well, at least it won't come as a surprise now!" Goku said brightly. As if waiting for the perfect cue to butt in, it was at that moment a voice from the sky spoke up.

"It's always a surprise." The Z fighters looked up as one man to see who had spoken. It was a tall black creature with hulking muscles, whose shiny skin was black and smooth. Or maybe he was wearing a reflective form-fitting jumpsuit. His eyes were pools of red, with neither iris nor pupil. He spread his arms wide, fingers extended. "Surprise!"

It was a comical entrance that none of the warriors found funny, Piccolo least of all. "That's him," he told the others, his voice grim. "That's the attacker."

"I thought you couldn't see anything definite!" Vegeta challenged him.

"I couldn't. There was nothing to see." Piccolo's sure voice somehow ended the argument. "But I know it's him."

"Well, then we know what happens next, don't we?" Vegeta muttered. Dende surprised them all by speaking first—and rather rashly.

"Excuse me!" he called up to the assumed villain. "As the Guardian of Earth, it's my duty to ask you what your intentions are, strange being!"

"Guardian of Earth," the newcomer repeated, rolling the words off his tongue. He grinned broadly. "Then you'll have to guard it from me! Because my name is Ful, and I'm here to have fun!"

"F-fun?" Dende was obviously confused. "What does that mean?"

"It means I'll do as I please with this planet and everything on it!" crowed the self-introduced Ful.

"No, you won't!" Goku yelled. "In case you don't know yet, the Earth has people who love and defend it! Like us!"

"Think you'll have 'fun' when we get our hands on you, wretch?" Vegeta threatened him. Ful flipped upside-down, still smiling.

"Fighting? Killing? Dying?" He laughed aloud. "Each more fun than the last!"