Somewhere in the Earth Kingdom:
As our lovely pair of siblings fought atop their poor little boat, the narrative is torn away, pulled back to the Earth Kingdom and a battle so monumental, so legendary, that even the great spirits themselves have gathered in the unseen reaches to watch.
On one side stood what was likely one of the largest armies ever assembled by the Earth Kingdom in a single field. It was a force numbered in the tens of thousands. Their synchronized march alone equated to a localized earthquake, a relentless drumbeat of impending violence. Among their ranks were strategically placed over a dozen earthbending masters—a fact that spoke volumes about the importance the Earth Kingdom placed on this engagement. Masters were a nation's most valuable resource; a single one could contend with an entire platoon of normal benders on equal footing.
On the other side, a couple of kilometers away, stood a single person. He was relatively tall, standing at just over 185 centimeters, with a lean yet powerfully built frame. His hair was as black as a moonless night, and his eyes gleamed with a piercing, golden hue like the heart of a sunset. He was clad in traditional Fire Nation armor, though his was completely blacked out, accented with additional elements: fingerless gloves boasting metal plating on the knuckles and fierce red dragon engravings etched upon the shoulders. (A little edgy in my opinion, but who am I to judge? It's not like he's my character). On his back rested a katana, its blade a deep crimson, its handle black, and upon that handle, the image of a dragon was intricately engraved.
This was Kai, the eldest son of Fire Lord Ozai, a prince of the Fire Nation, and the undisputed heir to the Dragon Throne.
Despite his youth of just seventeen years, he was undoubtedly one of, if not the, greatest firebender to ever exist. His control over the element was the stuff of its own legend. His raw power output dwarfed that of a trained bender, and he could unleash volumes of flame akin to a fiery tsunami. These monstrous qualities had the unintended side effect of superheating his flames into an unearthly, searing white color.
His royal status had also granted him the secret of lightning generation. At the age of ten, his father had personally taken up the mantle of teaching him this lethal art. Unlike fire, lightning demanded perfect self-control, and Ozai had believed his son, so accustomed to overwhelming power, would struggle. He was mistaken. Kai's control was preternatural, and he mastered lightning in a mere few months. Now, he could generate it faster than his father and with more devastating charge behind each bolt.
Since his entry into the army six years prior, he had made a meteoric rise through the ranks to the position of Vice Admiral. Although unstoppable in battle, a single shortcoming had kept him from the rank of Admiral or General: his overconfidence and brashness. He was known to charge headfirst into situations, a mind not yet cultivated for the complex chess game of large-scale warfare. He was the Fire Nation's ultimate superweapon, his sole mission to tear down any who stood against his nation and his family.
Now, as he watched the colossal Earth Kingdom army churn towards him at an alarming speed, a menacing grin split his features. "So the rockhead wants an all-out war, huh?" he mused to the empty air. "Then let's make an entrance worthy of the great spirits."
He began to run, then took a massive, bounding leap. He angled his body sharply and thrust his arms parallel to his hips. With a surge of will, he unleashed jets of compressed white flame from his hands and feet, rocketing into the sky like a vengeful star.
At the rear of the Earth Kingdom army, General Boqin spotted the glowing figure rocketing toward them. "Get ready! He's coming!" he bellowed. Four of the earthbending masters moved as one to the front. With a unified stomp, they raised a salvo of car-sized boulders from the earth and hurled them toward the flying prince with immense force.
Kai, seeing the projectiles streaking toward him, became a blur of motion, darting left, right, up, and down with fluid, impossible grace. Seconds later, the barrage ceased, and he emerged untouched. A younger soldier near the front cried out, "Damn it, not a single one hit!" A grizzled veteran next to him spat, "That attack wasn't meant to hit him, boy. It was to slow him down. The masters and the General know a few rocks won't end the Butcher."
Suddenly, Kai halted, hovering hundreds of meters in the air before the army. He raised both hands, arcs of blue-white energy crackling and converging between his palms, coalescing into an immense, throbbing ball of lightning. In one continuous, violent motion, he thrust his hands forward and released the cataclysmic bolt directly toward the heart of the army.
Some of the more experienced earthbenders managed to raise stone walls in a desperate attempt to shield themselves and those nearby, but their efforts were pitifully inadequate against the attack's suddenness and overwhelming power.
The prince's lightning tore through their defenses like paper and struck dead center in their ranks. A deafening CRACK-THOOM split the world, followed by a blinding flash and a shockwave that radiated outwards, swallowing a vast swath of the army in a storm of pure energy.
A few seconds later, the light died, and an awful silence descended, broken only by the moans of the damned.
The sight left behind was gruesome. At the epicenter was a deep, smoldering crater thirty meters in diameter. Everything and everyone inside that circle had been vaporized instantly, and they were the lucky ones. Radiating out from the crater's edge was a ring of hellish suffering: mangled bodies, soldiers screaming in agony from lost limbs, others blinded by the flash, most sporting horrific second and third-degree burns that blackened their skin. In one attack, Kai had killed more than fifteen hundred soldiers and incapacitated another eight hundred.
Some distance away, General Boqin was on his knees, trembling not from the shockwave, but from soul-crushing horror. "How...?" he whispered, his voice hollow and hopeless, utterly alien to his stature. "A tenth of my army... gone... with a single attack..."
A volcanic rage then erupted from his core, burning away the fear. He slowly rose to his feet, his voice a roar of pure defiance. "To hell with our plans! Soldiers of the Earth Kingdom! Even if we lose our lives today, we will put an end to this monster! ATTACK!"
Every remaining soldier capable of fighting unleashed their fury. The earth itself was torn asunder as a mountain of boulders, spikes, and shattered rock was hurled skyward. The barrage was so immense it darkened the sky, blotting out the sun as it arced toward the hovering prince.
Kai, seeing the literal avalanche of earth destined to crush him, did not retreat. Instead, he unleashed a torrent of white flame so vast it seemed he had tapped into the sun's core. Spinning with breathtaking speed, he wove the fire around himself, creating a swirling, miniature star, a blazing, impenetrable shield against the coming storm of stone.