Xiaya looked at his three children who were surrounded by a strong aura. If it was in the past, they would have been experts who could take charge of an area, but Xiaya's expectations for them were not only that. He had set the Super Saiyan transformation as a goal for his children.
"You all should join hands and attack me." Taking a few steps back, Xiaya said indifferently. He had to first get a clear understanding of the basic situation of his children.
"Okay!" Xiang replied loudly. His small eyes turned to his younger sisters, and then he attacked Xiaya fiercely together with them.
Perhaps, because they were children, their attacks were extremely straightforward, with almost no skills at all; they relied on brute strength to attack.
Naturally, such attack skills were overly simple, crude, and had certain feasibility in a situation of with a huge disparity in strength; however, the effect was bound to be greatly reduced. If one encountered an evenly matched or slightly weaker opponent, they would easily lose.
Xiaya watched their movements and shook his head, but then he revealed a faint smile. After all, they were still young and greatly pliable.
Xiaya's upper body turned, dodging three fair and tender fists brushing past his chest with a very small turn.
Xiaya crouched low, turned around and appeared by the children's side; then, he raised his palm, bent his index finger and lightly flicked the children's foreheads.
Bang! Bang! Bang!
A strange force penetrated their body, causing them to fly backwards and suddenly lose their strength.
"Boo hoo, it hurts!" Covering his forehead, Xiang cried out and bared his teeth, feeling weak all over his body.
On the other side, Xiili and Meifei were crouched on the ground, shouting. Xiaya would not show mercy to his opponents just because they were girls. Just now, his attack was extremely painful!
"Okay, I'm more or less clear of your strengths. Then, we'll begin training," Xiaya's calm voice sounded.
Xiang and his sisters immediately straightened their clothes and sat down properly, listening carefully.
"The first step is to learn to control your strength. The way you utilise your strength is—in fact—too awful, so you must first learn to restrain your Ki. Of course, you may have grasped it a little by observing others, but it is still very crude. You can deceive aliens who haven't grasped Ki, but it wouldn't work against ordinary experts."
Xiaya began to explain the process of training. His explanation went from basic to profound and touched the fundamentals. The three kids seriously listened. Due to his rich experience, Xiaya's explanations were precise, often piercing the key areas.
Of course, these were all theoretical stuff, and the key knowledge must be learned in actual combat. Thus, when he finished speaking, Xiaya let them attack each other and learn through experience from actual combat. First, he had Xiang and Xili join forces to attack Meifei as it couldn't be helped. Meifei's strength exceeded theirs by a great deal. If they don't join forces, they will have no chance at all.
In this fight, a lot of problems were revealed, and Xiaya corrected the issues in their techniques little by little.
Just like this, under Xiaya's guidance, the children slowly learned to control their strength.
...
While Xiaya was guiding his children on Planet Hongshan, far above in the North Area Underworld's dimension, Goku and others passed through the long Snake Way and finally arrived at North Kai's Planet; they intended to see Kai and train under his guidance.
One day, North Kai—who was wearing sunglasses—walked out of the small house and leisurely watched Krillin and others sweating profusely while training. Their movements were fluent as if not affected by North Kai's Planet's gravity, which was ten times greater than that of Earth's gravity.
North Kai said after sighing with emotion, "I really couldn't tell that you were Earthlings. After all, from what I remember, Earthlings should only be a very weak race. Is it because I haven't paid attention to them for a long time, and Earth has now become a High-level planet? "
"No, Earthlings are still very weak. Krillin and others are just a special case because they have been training in the Gravity Machine's environment. As for Senior Brother Goku, he is not an Earthling," Chi-Chi, who was sitting by the side, said.
North Kai propped his sunglasses in confusion, and asked in surprise, "Goku isn't an earthling? But he clearly looks like an earthling … Umm, could he be a Saiyan? Aren't Saiyans already extinct?"
If one had to pick a race that looked the most similar to Earthlings in the universe, then it would be Saiyans.
"Senior Brother Goku is indeed a Saiyan; moreover, Saiyans are not extinct. As far as I know, there is a planet where the Saiyan race resides in the far-off East Area. They are kind people."
"Is there such a thing? I'm not clear of the situation in East Area." North Kai nodded thoughtfully. "I didn't expect that an honest person like Goku would be a Saiyan… Saiyans can be kind? I never considered it before. "
"By the way, I have a secret skill which I am very proud of… Do you want to learn it?" North Kai suddenly smiled mysteriously and started to show off again.
"Kai-sama, what secret skill do you have?" Goku's ears were alert as he moved closer.
North Kai proudly said, "My secret skill is called 'Spirit Bomb'. In addition to using my power when attacking, I can also use the power of the entire planet. If I am sufficiently strong, I can even use the power of the entire universe."
"So powerful… Kai-sama, you must teach me!" Goku put his palms together and begged. After learning that North Kai had such a magical move, he felt an unbearable itch and immediately wished to learn the skill.
Seeing some activity on this side, Tien Shinhan and others walked over.
North Kai raised his chin and laughed heartily, "This is a technique that only people pure of heart can learn. Among the lot of you, only Goku and Chi-Chi are qualified, but I also have another martial art technique called Kaio-ken."
"Kaio-ken is a technique used to increase one's Battle Power several times over in a short period. It is a proud work of mine that I researched for many years, but it puts a heavy burden on the body. However, with your physical condition, using 2-times Kaio-ken will be very easy."
North Kai slowly explained the features of Kaio-ken, and everyone's eyes got increasingly brighter the more they listened. 'This secret skill is simply amazing.'
From North Kai's explanation, once experts like Tien Shinhan whose Battle Power had nearly reached 100,000—uses Kaio-ken—their Battle Power will directly soar to 150,000; If two-times Kaio-ken is used, their Battle Power will be 200,000. As long as the body can withstand it, Kaio-ken was the only way to fight by bypassing levels.
Goku and others stare at North Kai with scorching eyes. North Kai was enjoying it greatly as he nodded again and again.
Then he taught them how to use Kaio-ken. After he finished speaking, North Kai solemnly warned, "One thing you should pay attention to is that this technique will have a great negative effect on your body. When you use it, act according to your capability and never go beyond your body's limits, or it will collapse."
"Umm!"
They all nodded and went to the side to practice Kaio-ken.
Kaio-ken was extremely complicated, involving all aspects of the human body; thus, it was very difficult to train. The group had to research on a way to master the Ki flow method of Kaio-ken and prevent the powerful strength from causing the body to collapse after using it.
Seeing that Tien Shinhan and others were absorbed with their training on the Kaio-ken technique, North Kai nodded slightly, turned around and called Goku and Chi-Chi over. "Goku, Chi-Chi, leave the training of Kaio-ken on hold for now. I will first teach you Spirit Bomb, as learning Spirit Bomb will make it easier to use Kaio-ken."
Then, North Kai began to point out the execution method of the Spirit Bomb technique to Goku and Chi-Chi. Since it involved the energy of the planet's origin and could accidentally cause immense destruction, North Kai spoke very carefully.
Goku and Chi-Chi listened seriously, noting down the essential parts, and then they began to train. Just like this, the days passed, and they were unaware of the huge crisis that was gradually approaching Earth.