Don't let Dudley's wild look, wild words, and wild actions fool you; deep down, he was calmer than anyone.
After their brief scuffle, he knew he was no match for Hagrid in a straight fight. That last punch hadn't even used the Ripple technique, but Dudley knew even with it, he couldn't beat Hagrid head-on. The difference in their species was one thing, but the fact that he was still new to the Ripple arts was another.
Hagrid's magic might not have been much—he was, after all, expelled—but his real strength was far beyond that of a typical wizard. Just think of the pets Hagrid's kept: dragons, an Acromantula, a three-headed dog, and Blast-Ended Skrewts. The first two are, without a doubt, dangerous magical creatures of the highest order, classified as XXXXX. The three-headed dog's danger level isn't specified, but it's surely up there. As for the seemingly weakest creature, the Blast-Ended Skrewt, Hagrid bred it himself by forcibly cross-breeding a Quintaped (another XXXXX creature) with a Fire Crab. I've even heard that when he was teaching, he even tried to get a Chimera egg!
Considering he's mixed with a group of XXXXX-rated magical creatures, and even managed to forcibly breed a Quintaped and a Fire Crab, how much do you really think Hagrid lacks in strength?
To beat Hagrid, Dudley needed to be clever and quick. He had to finish the fight fast, before Hagrid had a chance to react.
Dudley launched a frantic attack on Hagrid's legs, a flurry of fists aimed squarely at the weaker points of his joints. He had to slow the big man down first. The skills from the "system" he was using seemed to cover everything but magic, and his vast knowledge of human anatomy was proving useful. Half-giant or not, Hagrid's joints were in the same places as a normal person's.
As Hagrid reached out to grab him, Dudley ducked and weaved, as slippery as an eel and as nimble as a monkey. He knew he couldn't be caught; a single抓would mean the end. In a brief moment of space, Dudley pulled a bottle from his shoulder bag, bit the cap off, and downed the contents.
The first potion: a substandard strengthening solution, which enhances the effects of other potions.
The second potion: a poor-quality Skelegro, a potion that can mend broken bones in a jiffy and even regrow ones that have vanished. Dudley's earlier attack had bruised the bones in his fists, and he needed to recover quickly. The Ripple art could heal bones, too, but Dudley wasn't skilled enough yet. Even the weakest joints were too tough, and his attack was damaging himself as much as his foe.
The third potion: a second-rate Blood-Replenishing Potion. His earlier "pulling off his tail" stunt had been a dramatic one, but he'd lost a lot of blood and needed to top up before he bled out.
The fourth potion: a poor-quality Essence of Dittany, for healing wounds.
With the four potions inside him, Dudley's face looked much better. The whole affair had been painful, but the pain only made the lesson more memorable. Then, he took out four more bottles.
This time, he didn't drink them himself. Instead, he hurled them at Hagrid. The fragile glass vials shattered on impact, releasing a puff of dusty, yellow-brown gas. They were four bottles of a concoction to slow a person down.
Of course, all of Dudley's potions were marked "substandard." He was, after all, self-taught and hadn't had any proper schooling. To have created a finished product at all was a sign of true genius. Even the great Potions Master Snape couldn't have brewed a finished potion on his own at that age.
Dudley also had another potion called "Muddleheaded Mixture" on him, which causes confusion, but he didn't want to face a truly enraged half-giant, so he didn't use it. It was a shame he couldn't brew more complex potions on his own yet, or he would have shown Hagrid what "stacking enchantments" was really all about. Potions may not be as spectacular as spells, but they can achieve the same results.
Just as he'd hoped, Hagrid's speed and reaction time slowed down noticeably. But alas, he was a half-giant, and his physique was far from normal. The potions made him sluggish, but not as much as Dudley had intended. Still, it was better than a spell, as a giant's resistance to magic is astoundingly high.
And this slowing was enough.
Dudley picked up the rifle from the ground. This time, he didn't shoot it. He grabbed it by the barrel and began his high-speed Ripple breathing. A warm, glowing power filled his body, gathering in his hands and flowing into the rifle.
The rifle itself didn't change, but golden arcs of electricity flickered along its length. In the daytime, you might not notice, but in the dark of night, it was quite obvious.
Dudley didn't bother to hide it. He held the rifle like a club and swung it with all his might, aiming straight for Hagrid's kneecap.
With a crash, the mountain of a man fell again. This time, however, it was much more serious than a simple fall; his bone was broken.
But Dudley's assault was far from over. He tossed the battered rifle aside and strode quickly to Hagrid's side. He widened his stance and lowered his centre of gravity, as if getting ready to perform a horse stance, all while adjusting his breathing once more.
This was Dudley's final trump card, the most powerful and highest-level skill in his arsenal: LV5 Iron Mountain Strike!
It was a move from the ancient art of Baji Quan, a simple, yet incredibly fierce and powerful move. With the system's improvements, its power was even greater. Its only drawback was... the rather odd posture required to perform it.
Dudley pressed himself against Hagrid, took a deep breath, and once again adjusted his Ripple breathing. The energy flowed through his blood, filling his body and concentrating in his lowered shoulder. Then, he released all of it in a burst of energy, driving his shoulder at a furious speed upward, at a roughly 45-degree angle.
Hagrid felt an unimaginable force slam into him, a brutal impact that seemed to shift his insides. The force was even greater than his own, and a sense of helplessness washed over him.
How could this oaf be so strong?
But... it wasn't over yet.
The LV5 Iron Mountain Strike was a combo move. Dudley lowered his shoulder again and struck once more, this time at a downward 45-degree angle.
"I rather liked the Iron Mountain Strike!"
Another impact...
Dudley's body began to move up and down in a rapid, repetitive motion, like a magical pile-driver. One, two, one, two, one, two! The terrifying power of a level 5 skill was on full display.
Then, an even more shocking sight took place. Hagrid's massive, multi-ton body was lifted into the air.
Not only Hagrid, but Dudley himself was stunned by the power, gaining a new respect for his level 5 skill.
So strong! So terrifying!
I love it!
It looked like a simple up-and-down motion, but it contained a complex array of techniques for generating and dissipating force. The most direct evidence of this was that Dudley didn't suffer a single injury from the strikes. Force is, after all, reciprocal. At the beginning of the fight, when Dudley had punched Hagrid, he'd badly injured his own fist. But the Iron Mountain Strike had no such drawback!
It was a perfect battle technique!
Hagrid's giant body crashed through the door, falling heavily outside.
Dudley stood over him, holding the broken door, looking down at Hagrid.
"You're not welcome here!"
"Now, beat it!"