A/N: Yeah, so this popped into my head fully formed a couple days ago. The action writing took me awhile, and the ending is a bit abrupt, but I think it turned out okay. Hope you enjoy!
Aang found Katara in the room where they practiced waterbending. It was her favorite room in the Upper Ring stone house they lived in when they traveled to Ba Sing Se; basins of water lined all four walls, and a large stone fountain gushed water in the center of the room. Through the windows on the far wall, the sky was blossoming into twilight. Katara had her back to him, and Aang watched for a moment as his wife twirled a thin stream of water in the air, forming it into fantastic shapes.
He crossed his arms casually in front of his chest and leaned against the doorway. "I thought I told you to take it easy."
Katara dropped the stream of water she was practicing with. "Aang!" She ran—well, waddled—over and embraced him as tightly as her pregnancy would allow. She was eight and a half months along now, and the nineteen-year-old Avatar constantly reminded her how beautiful she was.
"You're home early!" she said, brimming with happiness.
"Yeah," he sighed, running a hand through her hair, "But the meeting ended early today so I could go to the Spirit World tonight. It's the solstice." Now it was her turn to sigh. "But I can stay if you want!" Aang continued hastily, " I don't want to leave you alone or anything—"
"Go," she said, "I'll be fine." She patted her heavily swollen abdomen. "We'll be fine."
He sat cross-legged on the floor, assuming a meditative stance. "You're sure?"
His eyes only closed for a second before opening again. "Katara, don't stay up all night either, like you did last time. Get some rest, okay?"
"Okay. Don't worry about me, just do what you need to do." She knelt next to him to put her hand on his shoulder and massage it gently. He grinned, then closed his eyes, slowed his breathing, and resumed meditating.
Katara smiled. She loved watching him meditate. He was so peaceful. She matched her breathing to his, and listened to the gentle cascade from the fountain in the center of the room. Inhale, exhale. Inhale, exhale. Inhale, exhale….
The baby kicked inside her just as its father began to glow, interrupting Katara's concentration. Clumsily, she got back to her feet, went to their bedroom, and returned with a blanket and some pillows. If Aang didn't want her to stay up all night, then she would just spend the night with him.
Aang didn't so much as twitch as Katara snuggled next to him. She closed her eyes, blocking most of the glow, and drifted to sleep, her cheek resting against his knee.
It was the middle of the night when a loud noise jerked Katara from sleep. She rubbed her eyes and sat up. Aang was still glowing cross-legged next to her, in the Spirit World. What had made the noise?
Groaning softly as she struggled to her feet, she walked to the hallway, listening carefully for the source of the noise. When she passed the bedroom, she stopped.
"Look, I didn't mean to trip! The floor's shaped weird!" someone whispered. Katara's eyes widened. Burglars! She frantically tried to remember if the vase on the table inside the door still had water in it.
"Idiot! They're not even in here…why wouldn't they be in the bedroom?" Katara froze.
"Well, the Avatar's supposed to be meditating."
"Search the house! We need to warn the others—the wife's not here either!" Katara gasped. She had to get back to Aang—he was totally helpless right now—
Strong arms wrapped around her from behind, pinning her arms to her side and stifling her scream.
"I've got the wife!" the gruff voice behind her called. Katara thrashed in his grip wildly, freeing one arm just as the two men in the bedroom opened the door. The large flower from the vase in the bedroom disintegrated as the water in and around the plant slashed past the two men's faces and froze around the head of the man holding her. He relinquished his grip on her as he struggled to get the ice off so he could breathe, and Katara dashed as quickly as she could back to the waterbending room.
She entered to find four men helping four others climb through the far windows. Immediately the water in the fountain surged towards them, knocking the four still outside back to the ground and freezing the other four solidly to the edges of the windows.
Katara felt heat an instant before she dodged to the left, barely avoiding a fire blast from behind her. Three, no four more men appeared in the doorway, two of them holding fire daggers. Two firebenders…
No, five firebenders, Katara realized with horror as she saw three of the men frozen by the windows melting through the ice. The water in most of the basins rose and lashed at the two firebenders at the door as Katara's eyes narrowed. A fleeting long-ago memory of a younger, different Zuko snatching Aang from her at the Spirit Oasis flitted through Katara's mind. She would not let them take Aang.
She pinned the two remaining men to the door with another wall of ice as the firebenders at the window melted through. Two of the men climbing through the windows launched boulders from the stone floor at her. Her water whip deflected the stones enough to hit one of the two firebenders behind her instead. She mentally counted the remaining attackers. Four firebenders, two earthbenders, and three others remaining.
Katara slashed her water whip at the only man left at the door—a firebender—extinguishing the fire he blasted at her and slicing open his hand. He yowled in pain, distracted for a moment, as Katara placed herself between Aang and the men at the windows and summoned all the water in the enormous fountain to swirl around herself and the still obliviously glowing Aang. The water sprouted tentacles, forming into an octopus stance.
The men quickly surrounded her, launching earth and fire at her. The three nonbenders were armed with swords and knives, but were unable to penetrate the watery wall. Katara absorbed the blows with the water, but she could feel her energy slipping. Her pregnancy had already made her tired before the fight, but now she was exhausted.
The four firebenders took positions around Katara's water form and blasted fire straight at it. Katara tried in vain to save some of the thinning wall of water, but it sizzled away until one of the nonbenders broke through, snatched her by the arm, and dragged her away from Aang's body.
"LEAVE HIM ALONE!" she screamed, slashing at her captor's face with her fingernails. She drew blood and earned a heavy blow to her cheek. She stumbled, and the nonbender took the opportunity to wrap one arm around her waist and press a knife to her throat.
The firebender whose hand Katara had sliced open earlier seemed to be the one in charge. "Good, you hold her," he nodded to the man holding Katara, "You three, go find something to use to tie her." A nonbender and the two earthbenders nodded and left. "The rest of you, start chaining the Avatar." The remaining nonbender distributed the chains he'd brought in with him through the window to the two firebenders. Katara struggled in vain. The knife at her throat cut into her skin slightly, drawing blood, but she didn't care. It had happened again—she had been unable to protect Aang while he was in the Spirit World again.
"Thank you, Avatar Yangchen." Aang bowed to his predecessor. The old nomad smiled.
"You are welcome, young one. You have learned quickly, even though you have not had real air to work with." After consulting with Roku and a few other past lives about ideas for trade negotiations, Aang had asked Yangchen to teach him the 36th level of air mastery, which he had not learned at the temple before he ran away. The kindly air Avatar had described it to him in detail, demonstrating as best she could without any actual air, as there was no bending in the Spirit World.
"Be sure to practice with real air when you return," warned Yangchen, "And be sure to teach it to your children so the cycle can continue."
"So does this mean you know if my child is an airbender?" Aang asked hopefully.
"I didn't say that," Yangchen smiled, "But the chances of any child you have becoming an airbender are quite high. I would expect many airbenders running around before long. Goodbye, Avatar Aang."
"Goodbye, Avatar Yangchen," said Aang, returning her smile. Avatar Yangchen faded into the fog. Aang turned to the ancient archway behind him and walked through it to return to the mortal world.
Aang's sense of peace quickly turned to confusion as he returned to his body. The instant his tattoos stopped glowing, a voice yelled, "Quick, get his legs! He's waking up!"
Who were these people? What were they doing here? Where was Katara?
"AANG!" he heard Katara scream to his right. Immediately he reached towards her, but his arms were chained behind him. Adrenaline shot through him, blocking all thoughts but one: they were under attack.
In less than a second Aang kicked his feet up into the air, smacking the heads of the two men about to chain his feet as he launched into a backwards somersault, ending upright on his feet. The stone floor began to tremble as he prepared for a massive earth wave.
"Stop, Avatar, or she dies!" yelled a man with a bloody hand. The impromptu earthquake stopped immediately as Aang froze. The man holding Katara tightened his grip on her accordingly. Aang stared at the knife. He could already see blood on Katara's neck, and could feel his own blood beginning to boil. Otherwise, she seemed alright, although bruised and sweaty.
"What do you want?" he said with gritted teeth.
"The Gaoling Trade Treaty you're opposing passed."
"That treaty is unfair," said Aang, eyes darting through the room. "The tariff the Fire Nation would put on the Gaoling merchants is too high. Even Fire Lord Zuko agrees with me."
"Fire Lord Zuko is a traitor to his nation," the man spat.
"And how is capturing me going to get that treaty passed?" Aang demanded, spying a small puddle the size of his palm on the ground.
"I'm sure the Fire Lord and the Earth King would pay a fortune to get their peacekeeper back," said the man with the injured hand, his lips twisting up slightly, "Either way, without you that treaty will probably pass."
In one quick movement, Aang leaned back and kicked sideways with his foot. The palm-sized puddle zoomed through the air and covered the knife next to Katara's throat, freezing around the blade to render it useless. Aang's foot came down with a stomp, forcing two walls of earth to spring from the floor and slam the man holding Katara between them, sandwiching him.
The leader with the injured hand leaped into the air, flipping into a fiery kick. Aang filled his lungs with air and blew, barely keeping himself from being scorched and blasting him backwards into the far wall with a grunt. Katara hurried to his side, bending as much water from the air as possible into a usable stream. She slashed the foot-long stream at the chains on Aang's hands while he raised an earth wall with a stomp to block fire blasts coming from the two men left in the room.
"Are you okay?" asked Aang breathlessly.
"I'm fine, there's two more earthbenders and a swordsman in the hall—" The other three men entered through the door just as Katara finished cutting through Aang's chains. He used his suddenly free hands to crumble a boulder thrown at them as one of the earthbenders sunk his earth wall back into the ground. Katara hastily pulled more water from the air as Aang blasted fire at the three newcomers with one hand while encasing the firebender leader up to his neck in earth with the other. The air was thick and wet and almost steamy from all the water that had evaporated earlier, and Katara found it easier to pull water from the air than it usually was without the full moon. Soon she had enough for a water whip, which she hastily used to yank the knife the nonbender had thrown at Aang out of the air, then wrapped the water around the attacker's leg to throw him bodily into the wall, where he crumpled and stopped moving.
While Aang dodged the attacks of two earthbenders and the remaining firebender, Katara continued using the water in the air to grow her water whip. She wrapped it around the leg of one of the earthbenders, intending to smash him into the wall as well. Before she could do that, the earthbender twisted her into the ground. At the last second Aang whacked the firebender in the head with a boulder and turned to keep the earthbender from burying her completely. The remaining earthbender used the distraction to bring their firebending leader back to the surface.
Of the twelve men who had originally attacked their house, only the two earthbenders and the firebender leader remained. Katara now had enough water to freeze someone to the wall, but she would then be out of water. Her entire body was aching now, and the baby had not moved since the fighting had started, which scared her. Aang sensed her exhaustion, but was too busy deflecting fire and earth attacks to do anything.
Then the three benders changed tactics. Aang took a solid stance as the two earthbenders worked together, sending wall after wall of earth crashing at him from different directions, trying to squash him between their walls. The firebender advanced on Katara, who glared at him in rage and slashed at his face with her water. He responded with a wave of fire, evaporating some of the water. Undeterred, she twisted the stream around her, deflecting small staccato fire blasts he punched at her.
After smashing nine sets of earth walls, Aang jumped to allow the tenth set to smash together under him and blasted a powerful gust of wind to the earthbenders on either side of him, smashing both into the wall and out of consciousness.
As if to reassure its mother it was still alive, the baby shifted, pushing against Katara's ribcage. Katara gasped, partly in shock and partly from the pain, finding it even harder to breathe than usual. Consequently she failed to dodge the last fireball. It slammed into her shoulder, scorching her and knocking her to the ground.
With the help of airbending, Aang caught her before she hit the ground. "Katara?"
"Baby—ribcage," she gasped. Aang laid her gently on the ground.
The firebender yelled, "That's for my hand, you—" Four earth walls rose, boxing him in. Raising his fists, Aang carved one more slab of stone from the floor and dropped it on top, sealing the firebender in a solid earth cage. Aang's fist tightened, and the earth cage grew smaller and smaller, until the man inside must have been completely immobile.
It was a few minutes before the baby finally let Katara breathe normally again.
"Another fine Upper Ring mansion ruined," Katara laughed softly, indicating the room. The once peaceful, calm, zen-like space was now more rubble than room. The fountain was destroyed, every wall was heavily dented, the stone floor was virtually gone, and chunks of the earth foundation were missing completely.
"Toph will be upset she elected to stay in Omashu," Aang smiled, cradling her in his lap.
"Yeah, she missed all the action…."
The worry shone from Aang's eyes. "Are you okay? Did they hurt you? Your neck was bleeding…"
"Just a scratch. I'm fine. You?"
"I'm fine." He sighed. "I'm going to have to talk to Zuko about stricter background checks. Their leader was one of his lieutenants."
"How about we demand Zuko let us sleep in his room at the palace as retribution?"
"Sounds good. He'll have someone to look at your shoulder too. I'll run us over there." Aang staggered to his feet, carrying Katara in his arms.
"I'm sorry I'm too heavy."
"Hey, if the baby wasn't a future airbender, you'd be even heavier."
"Is it an airbender?"
"Avatar Yangchen thinks so."
"Yangchen….pretty name….." Katara said dreamily, nodding off to sleep.
Carrying his wife, Aang summoned his native element, and took off running.