Percy has seen and experienced many things in his life.

Monsters attending school? Checked.

Gods with anger management issues? Checked. They have Dual Aspects Disorder? Double checked.

Annoying step-siblings? Checked. Blond Superman? Checked.

One-eyed brother? Checked. A Cyclopes trying to marry his best friend of a satyr? Checked.

Getting dumped by a girl he never dated? Checked. A Titan-that-was-somehow-his-love-interest suddenly returns with his supposedly dead friend? Oh yes, checked. And boy, was that awkward... Wait, we're going off topic.

Who's we? Anyway...

His nosebleed awakens Mother Earth? Definitely checked.

A talking sword? Yeah, checked.

Suffice to say, nothing surprises Percy these days. Not even a mechanical dragon that is also a ship.

When Aang glided back to join the group and mentioned that they had a big problem, he couldn't imagine anything in this world that would pose a problem bigger than the serpent back at the Pass.

At first, he thought the problem was the hundred-meter tall wall looming over them, sheltering their eyes from the glaring sunlight. The Outer Wall of Ba Sing Se reminded Percy of a famous wall in China but he couldn't really remember the name, still, he wondered how they would enter the city with the towering fortification in their way. Then, Toph and Aang started making identical circular motions with their arms, bending the very earth they stood into a makeshift platform to transport the group to the top of the Wall. It was like riding the magical elevator in the Empire State building. Just without the safety features.

"Now what's so big that Appa has to wait?" Sokka voiced the question probably on everyone's mind.

With that Aang pointed to his right and six pairs of eyes followed the direction. Percy caught sight of the dust storm heading in the direction of the wall.

The issue was that dust storms would move like a large cloud gobbling everything in its path. This 'dust storm' moved in a V-like formation, and sea-green eyes widened when Percy noticed the 'Big Problem' the bald boy was referring to.

Of all the things that weren't supposed to exist, who on earth builds an oversized Drill?!

The demigod almost gave in the urge to question whether the Mist was playing tricks on his mind, or if someone from Hephaestus cabin was just having a laugh, but then zipped his mouth when he remembered that he was on some other planet that resembles Earth during Ancient China where both the Mist and the Olympian Pantheon does not exist here.

But Spirits do. Iroh said it. Maybe there's a Spirit for fire, metalworking, stone masonry, forges and the art of sculpture. That's the only explanation. It has to be.

Percy was snapped back to reality when Ying wailed despairingly about 'no one being safe despite reaching Ba Sing Se' and huddled with her family. Then an unfamiliar voice called out to them.

"What are you people doing here?" Everyone turned to see two men clad in identical uniforms shaded in dark forest green and conical helmets that had a light green feather on each of them. The first thing Percy noted was that they were both barefooted, feet only wrapped in cloth but leaving their toes exposed.

The same man who called them out pointed in the general direction of the group. "Civilians aren't allowed on the Wall."

The son of Poseidon was about to roll his eyes and make a snappy remark that he wasn't a civilian but Aang stepped forth to introduce himself. "I'm the Avatar, take me to whoever's in charge."

Percy took note of the serious expression on Aang's face. Guess someone's getting back in his groove. His eyes darted towards the refugee family that followed them, and back to the two soldiers. "Let's not forget to bring the refugees to safety, first."

The two soldiers shared a look, as if psychically debating about something. Five seconds passed and the mental debate ended, resulting in one of them calling for two more soldiers to escort Ying and her family to the 'transport'. Percy considered joining the family so he could possibly catch up with Zuko and Iroh faster, but another look at the large drill made the decision for him.

Ying and her family expressed their gratitude to the group as they split from Aang, his friends and Percy.

The two soldiers who encountered them first guided the remaining members of the group to a structure on the Wall that looked like a watchtower. Once in, they were introduced to a middle-aged man sitting near the tall arches that served as pillars and wall to the structure. He had a different outfit from the rest of the soldiers stationed there, donning golden skull-like shoulder plates (Percy shifted uneasily as it reminded him of monsters but did his best to hide his discomfort), and a sage green cape. The cape gave Percy the impression that he held a high ranking position, and his theory was confirmed when the man introduced himself as General Sung.

"It is an honour to welcome you to the Outer Wall, young Avatar," Sung greeted Aang and Percy's eyes narrowed at the levity from the confident General. He bit his tongue to swallow a retort when he heard a 'but' coming from the man in charge.

"But your help is not needed," Sung deadpanned.

Bingo.

Aang and his friends, however, were shocked at the announcement. "Not needed?"

A black eyebrow arched as Percy listened to Aang expressing his disbelief. Apparently being the all legendary figure of 'peace and balance' that is the Avatar, Aang was used to being the individual that people sort after to solve problems beyond their own capabilities. And now perhaps he experienced having his offer to help being rejected for the first time.

"Not needed," Sung repeated with a smile, seemingly unaware of the near-incredulous tone that the young airbender used. He stood up from his seat as he continued. "As a matter of fact, I have the situation under control."

Percy let out a snort at that. "Yeah, because everyone who says that has everything 'under control'."

Katara, Sokka and Aang's eyes were round at the evident disrespect that their towering companion showed to the Earth Kingdom General, while Toph grinned at the remark. The other soldiers were less amused, narrowing their eyes at the stranger. Sung turned his attention towards Percy, the smile on his face fell slightly as if showing he was unamused.

"And perhaps who might you be?"

Percy opened his mouth to retort at the condescending tone that the high ranking official laced in his words but Katara stopped him, stepping forward while placing an arm in front of the demigod and speaking out on her own.

"Forgive our companion's lack of... courtesy, General Sung," the waterbender tried to find the words to reason with the General. "But he means no ill will with his words. He's just quite... blunt with his words." With that, she snapped her head around to glare at Percy, who ignored the urge to roll his eyes but gave a shrug in response.

"Now, now, there's no need for such rigid formalities," General Sung replied with a toothy grin to the assembled group, Katara's words enough to quell whatever anger that could have risen within him. He gestured to the exit and began walking towards it. "Now back to the topic, I assure you that the Fire Nation cannot penetrate this Wall.

Many have tried to break through it, but none have succeeded."

"What about the Dragon of the West?" Toph crossed her arms as she questioned Sung's statement. "He got in."

Percy's lips twitched upwards as the confidence General Sung adopted wavered slightly as he sputtered to find a reply to the unexpected, though he quickly gathered himself and turned to face the group again.

"Well, technically yes. But he was quickly expunged," he raised a finger to make his point.

Percy did not miss the disappointed look on Toph's face.

"If one guy can get past your defences, what makes you so sure a machine more than a mile long won't do the same?" Percy asked sceptically. "It's shaped like a dam drill, and drills are supposed to... you know, drill holes into walls. And then you'll have a leaking dam to be concerned about."

No one understood why Percy was smiling at this point, nor what he meant by that last sentence, though Toph agreed with the point that he raised.

"He's right, that makes the drill a problem."

"Not for long," once again, General Sung shot down their concerns as he strode towards a monocular set up on the wall facing the desert. "To stop it, I have deployed an elite group of earthbenders called the 'Terra Team'."

"That's a good group name," Sokka commented and held his chin between the bent forefinger and thumb. "Very catchy."

Percy and the others stood behind General Sung, who watched his 'Terra Team' attack the incoming Drill and the tanks supporting it through his monocular. Sea-green eyes watched without the assistance of a telescope as some of the tanks were swept back by large chunks of earth and the Drill suddenly halted in its place as the earth shot up again in spikes, slamming onto the large machine.

That lasted less than five minutes. The spikes crumbled, allowing the drill to continue its journey and within another ten minutes or so, General Sung straightened up and started flailing his arms, any sign of his previous confident conduct all but evaporated as panic took over the middle-aged man.

"We're doomed!"

Sokka was the first to react to the General's outburst, slapping the man across his face. "Get a hold of yourself man!"

"That was a lot of control you had, General," Percy deadpanned.

"You're right," General Sung looked abashed as he rubbed his swollen cheek. "I'm sorry."

"Maybe you'd like the Avatar's help now?" Toph suggested.

Sung turned towards Aang, dropping his head at the same time. "Yes, please."

Percy almost rolled his eyes at the comical display as this supposedly high ranking official carried himself. As far as he remembered, Praetors always had an air of authority or just confidence that allows others to put faith in. General Sung had neither.

Hades, now I sound old.

"So the question is," Aang's voice broke the silent atmosphere as they watched the Drill closing in. "How are we gonna stop that thing?"

Seeing Aang and Katara looking at Sokka expectantly, Percy did the same. The Water Tribesman noticed the eyes on him, and stared back curiously while crossing his arms in front of his chest.

"Why are you all looking at me?" Sokka was both confused and curious.

"Everyone was looking at you. So, I just joined them."

"You're the Idea Guy," Aang ignored Percy's remark and answered Sokka's question.

"So I'm the only one who can ever come up with a plan?" Sokka raised his eyebrow at the designation. "That's a lot of pressure."

"And also the Complaining Guy."

Sokka couldn't help but raise his chin slightly at Katara's comment. "That I don't mind."

"Well, whatever you mind or don't mind, Brainy, you've gotta come up with a plan," Percy stated as he stalked towards the edge of the wall. Sokka gave him a sceptical glance.

"Oh, and what are you going to do? Lift those tanks with your non-waterbending-bending?"

Percy kept his eyes on the large drill and its remaining tanks supporting it by its side, refusing to glare at the other boy's weird description of his powers. He took a deep breath, allowing the air to fill his lungs and fuel his muscles with oxygen.

"Buy you guys some time to save those elite soldiers and come up with whatever plan you can to take down that oversized drill."

"How?" Katara asked, exasperated. "Whoever was in that Drill was strong enough to take down the 'Terra Team'. You are just one man."

Everyone was confused when they saw Percy smile. It wasn't the same smile he had which warned people that he spelled trouble. Instead his lips were tight and thin, barely reaching his eyes, showing a tired and weary smile. It aged Percy by almost decades, making his appearance almost as old as General Sung without the saggy skin.

"Then it's a good thing they never met me before."

"But there's no water around here!" Aang tried to bring Percy to his senses.

"A machine that big would need to run on some sort of coolant to keep it from overheating and breaking down," thank the Gods for Leo's many impromptu lectures about cars and engines. If Percy was correct, then he'll have a water source. "I can work with that."

If not, there's also the water behind the Outer Wall, which Percy guessed was for agriculture purposes. Yeah, let's try not to resort to that.

"But that's if you get close!" Sokka cut in. "Did you so happen not see the tanks that are still flanking the Drill?"

"Like I said," The look on Percy's face hardened and everyone zipped their mouths. "I got this."

Aang wanted to stop Percy from making such a rash decision. Sure, they only met recently, and yes, this man was clearly powerful in his control of water – maybe as, if not more, powerful as Master Pakku (not that he'll say it to the old Waterbending Master's face) – and was skilful enough to fight off his team, but this was a battle against a sophisticated mechanism that was made of an element no one can bend. Heck, like Sokka said, there's even the tanks that will need to be taken into consideration. The firebenders will roast Percy alive.

I'm the Avatar, I need to keep everyone alive. I need to –

A hand on Aang's shoulder snapped him from his trance, and he lifted his head for charcoal-grey eyes to meet sea-green. Percy's expression had softened, allowing Aang's racing thoughts to slow down.

"I'm counting on you," Percy said, and for the first time Aang noticed the firmness in the man's eyes. The Avatar saw Percy's conviction, it was as if the man had fought wars and survived it, like he encountered insurmountable odds and still came up on top.

Somehow, Aang was certain that Percy wasn't running to his death, and that he'll return just fine. The airbender took a deep breath, and nodded. He returned Percy's smile with a small smile of his own.

The hand left Aang's shoulder as Percy walked towards the edge of the Wall.

"Aang!" Katara cut in. As much as she distrusted Percy, no one should run into battle like that. It was suicide. "You can't just –"

"Percy's right, Katara," Aang interrupted Katara. "Everyone's counting on us. And we need as much time as we can get."

The waterbender cannot believe the words she heard. She snapped her head towards her brother. "Sokka, help –"

"What do you need us to do?" Sokka's expression was hardened with his own conviction.

Percy kept his gaze on the Drill. "Get as many of the soldiers down there back to safety. The survivors will most likely have some story to tell. And there's one more thing," He turned his head slightly, allowing them to see the same troublemaker smirk now plastered on his face.

"Wait for my signal."

Before anyone can ask what the signal is, Percy jumped off the Wall.

The wind in Percy's face was picking up as he descended, yet the demigod felt nothing. Instead, he felt something churning in his gut and the same voice whispering into his mind.

Feel the water around you, warrior. Command it. Command the elements. They are yours to bend.

He could feel the same tug in his gut, and Percy reached out to it. Just before he could hit the ground, water erupted from it, reaching out and engulfing him. Percy felt his body refreshed and his mind cleared. He could see the tanks guarding the Drill, and the holes in defences left from trying to make up for the other armoured vehicles that were damaged in their confrontation with the Terra Team. Smiling to himself as his feet touched the ground, Percy fished Riptide from the cloth that was his belt.

Then, he charged.

Up at the Wall, Sokka and Aang's mouths were agape.

"Just how powerful is he?" Aang asked.

Katara narrowed her eyes at the sight of the water erupting underground. She had never heard nor encountered anyone that had that much control over water. In fact, he was unlike any waterbender she knew. He showed zero little to no fluidity as he bent the water, looking as if relying on sheer power instead, which was completely different from the scrolls nor waterbenders in the Northern Water Tribe.

Maybe he is telling the truth. He could be not from any of the Water Tribes we know of.

"Hey guys," Sokka spoke up as he watched from the monocular. "Was Percy ever carrying a sword?"

"A sword?" Katara's interest was piqued. During their short time travelling together, Katara had never seen their mysterious companion carry any weapons. In fact, the only weapons the group ever had in hand were Sokka's boomerang, Suki's warfans, and Aang's staff – though the latter was mainly used for air travelling more than self defense.

Sokka motioned for his sister to have a look from the monocular, so she did. When she placed her eye behind the lens, everything from a distance was enlarged. And at the focus of it was Percy who was indeed holding a sword.

Even from afar, the young waterbender could see the odd shape of it.

"It's... weird," She muttered under her breath. Sokka heard her and he got excited.

"I know!" Her brother exclaimed, and Katara thought she imagined his voice sounded higher than usual. "It looks like an ordinary jian, but it's shaped like a leaf instead of being straight! Oh, and have you noticed the golden glow it gives?"

Katara peeled herself from the monocular to look at her enthusiastic brother, arching an eyebrow at the older teen who looked like he was trying not to jump up and down. "Golden glow?"

He nodded so fast Katara was worried his head was going to fall off.

Strange. She looked through the lens again, keeping focus on the sword in Percy's hand. And indeed, his sword emitted a soft golden glow. The girl wasn't sure if it came from reflecting the sun. She watched as Percy stopped running towards the Fire Nation army like the one-man army he is. "What is he doing?"

Unaware of the watchful eyes from the top of the Wall, Percy stopped in his tracks. Sparing a glance of the Outer Wall of Ba Sing Se behind him, and content with the distance he had put between himself and the city, the demigod returned his gaze back to the approaching army in front of him. The entire time his gut rumbled, as if eager to carry out the brief plan he had in mind.

It wasn't a plan per se, but Percy knew what to do. The demigod lifted his left foot as he threw caution to the wind, and uttered a silent prayer. Even though he was pretty sure the gods can't hear him from faraway, he reached towards the sensation in his gut.

One of his father's domains.

His gut rumbled harder as he slammed his foot onto the earth below. The ground started shaking.

Poseidon.

The quake became more violent as he focused on the rumbling right beneath the advancing vehicles, away from the Wall or the 'Terra Team' as to avoid any collateral damage. Then, the very earth split, cracks forming underneath the Drill and the tanks. Some became fissures, deep and wide enough to trap the latter in their place, and forcing the soldiers to exit the trapped machines.

The Earthshaker.

Percy allowed the twitching sensation on the corner of his lips as it formed a smirk when he saw the Drill suddenly stopped in its tracks, the head that was shaped like a drill bit no longer rotating. The smirk only grew wider as soldiers in red armour similar to the ones he met on the Fire Nation Ship being forced to exit their trapped machines to continue their march. He promptly made a mental note to remind himself in the future to burn food as tribute to whoever had assisted him.

Seeing the red-armoured soldiers rushing towards him, Percy charged into the heat of battle.

"He's an earthbender?!" Katara exclaimed, having witnessed the events unfold below. Sokka gave his sister an incredulous look.

"I thought he was a waterbender."

"Then how do you explain why the earth shook and ground split?!" She snapped. Sokka didn't look shaken by the question.

"Friction from tectonic plates getting stuck on the edges underground releases energy that travels through the earth up to the surface."

"You can't explain everything with your science, Sokka!"

Aang kept an impassive expression on his face at the newest revelation of Percy, ignoring the outburst from the Water Tribe siblings with thin lips. "I think that's the signal." He turned towards his group of friends who looked at him having stopped their own bickering. Regardless if Percy can bend two elements or one, the man is facing the Fire Nation alone for the sake of the Avatar and his friends. "Let's go save the 'Terra Team'."

oOo

Amber gold eyes narrowed at the recent turn of events, the only hint to any show of emotions that could only mean annoyance while the elderly man standing in the centre tried to rally his engineers around the control room as they scrambled to find a solution to their... dilemma.

To say that Princess Azula was unimpressed would be the understatement of the Hundred Year War.

The Fire Nation's many attempts to capture Ba Sing Se, the impenetrable capital of the Earth Kingdom had ended in failure since the very first try. The closest they ever came to seizing it was when her uncle, General Iroh had broken past the Outer Wall. But even then, the troops had been withdrawn for reasons unknown at the time. Eventually, it was found out that the 'great' Dragon of the West abandoned the siege upon learning that his son, Azula's eldest and only cousin Lu Ten, died in battle causing the old man to lose all will to continue the good fight.

Tch. Sentiment.

Princess Azula had been brought up learning one important lesson: respect is given to those who succeed, not those who fail. Since young, her father – the great Fire Lord Ozai – gave her his approval for she is deemed more talented and more successful than Zuko, her weak failure of an elder brother. From then on, she only knew victories, never failures. Even the rare unwanted obstacle in her plans would only be treated as a minor setback.

That is exactly how she intends to treat the predicament she found herself in. A minor setback.

War Minister Qin had claimed that the Drill to be a 'feat of scientific ingenuity and raw destructive power'. The metal used to build the very mechanism Azula, the War Minister, her friends along with several hundred soldiers and engineers found themselves in, is impervious to any earthbending attack by the soldiers of the Earth Kingdom defending Ba Sing Se. This was proven when the sole attempt to stop the Drill by the 'muscly guys' – as described by Ty Lee – was thwarted. As an added bonus, both Ty Lee and Mai made short work of the attacking earthbenders by defeating them in mere minutes, once again proving themselves capable friends worth accompanying her.

So, what she is currently hard to understand is how could the Head of the Fire Nation Military's Technology be so incompetent that he failed to account for the possibility of the Drill suddenly shutting down after an unexpected violent earthquake. There were even reports coming in from the engine room, engineers panicking and informing that there has been some damage to some of the coolant tanks, leading to leakage. The damage had appeared minor at first, until one of the tank rooms was flooded and almost trapped two engineers inside. Accordingly, it may take a while to restart the machine to prevent the occurrence of the engine overheating and setting the Drill and everyone in it on fire.

No doubt that this stall would provide time for the Earth Kingdom forces to regroup and formulate another plan to repel the Drill.

The disapproving glare that she sent War Minister Qin's way when the updates flooded them was enough to make the grey-haired man sweat. He blamed it on the lack of ventilation in the control room though.

Thinking back, Azula remembered hearing Ty Lee off-handedly mention seeing a man standing between them and the Wall right before the earthquake.

"His aura is blue, but it's also green. Very blue and green. Like the sea!"

She tried ignoring the 'aura' remark that her friend had excitedly made, filing it as part of 'Ty Lee's Airheaded Ramblings'. But for reasons unknown the back of her mind was sounding in alarm, as if warning her of something. Whatever that 'something' is, she couldn't wrap her fingers around it. Seeing no point nor progress from dwelling in her memories and the alarm blaring in her mind, she focused on the reports coming from the other tanks stating that some soldiers have been deployed to engage with the man in their way.

Nevertheless, he is but merely one man standing against the might of the Fire Nation. His resistance would only prove futile.

Even if the Earth Kingdom forces return to battle, she will make short work of their efforts.

After all, it was but a minor setback.