A/N: This is book five, chapter seventeen of the story. Part I of the finale. Aang and Katara are finished with their mission, but they are still trying to find each other. But things get worse when Aang runs into trouble with Yinyang and the Nightmares he defeated. Aang falls into a deep slumber and while he's dreaming, he learns about Yinyangs past. After all that, Aang becomes trapped in the Nightmarish Abyss.
Chapter 17 - The Nightmare part I - The Nightmarish Abyss
Aang flies on his glider through the dream portal, in search for Katara. Aang flies until he arrives at the Southern Air Temple. Aang lands, but is surprised at his arrival. "The Southern Air Temple? ...What am I doing here?" Aang walks up for a moment. "Is Katara here? ...No, she can't be. I've defeated the five Nightmares, but I don't think Katara would be anywhere around here so...why am I here?"
"Boy, you still haven't figured it out?" A voice says. Aang was surprised to hear it. "It took us a while to lure you here. We sure went through a lot of trouble to get you here."
Aang turns around to find Azula. The strangest thing about Azula is that this time, she looks calm like, almost like she's the Azula that was before the Boiling Rock incident. "You? ...You're apart of this?"
"That's right, avatar." Azula says. "Like my father, I am a dream version of myself."
"What's going on here?" Aang asks.
"It's so sad that you haven't figured it out." Azula says. "You've defeated the Nightmares, but you have yet to find your little friend. So...'Why are I here and why am I not back on Avatar Island' you might ask." Aang just looks confuse hearing that. "The answer is very simple. You are never gonna wake up! Not even your dream spirit friend isn't gonna help you."
"What do you mean?" Azula asks.
"You haven't noticed anything? The airbender? My father? You being separated by your friend?" Aang doesn't say anything. "Well, then...how about I enlighten you?"
Azula firebends a ring of fire around Aang. At first, Aang cowers to protect himself, but then notices all that fire reducing, turning into the Nightmares both her and Katara defeated. Those that Katara defeated were a surprise to him, even since he never faced them. Aang turns around to see Yinyang. Yinyang reaches her hand out to Aang. "Come with me."
Aang was confused, but then, he suddenly gets very drowsy. Aang looks back at Azula, who is smiling evilly and laughs a little at Aang. "Pleasant dreams, Avatar." Aang falls into a deep sleep.
In the dreams, Aang falls into darkness. He slightly opens his eyes noticing that he's slow falling. Just then, the darkness fades and reveals a room where Aang once saw on the day he was born. Aang stands up, then he sees his parents, holding him. At first, Aang smiles, but then notices his 'mother' was grunting in pain. "Wait! There's still another one!"
Aang was shocked to hear that. But, after a few moments for the miracle of life, another baby came. The father holds it in his arms. "It's a girl...What do you want to name it?"
The monk that was training Yinyang in the dream Katara was in takes the baby. "Well. How about we call this one...Yinyang."
Aang gasps hearing that, then he suddenly becomes pale. Aang loses his balance then falls back. "So, now you know." Yinyang says. Aang turns around to see Yinyang. "I am you twin sister."
"H-h...how come I never knew?" Aang asks.
"The monks took us from our parents and made us go our separate ways." Yinyang says. "I always knew you were my brother, but I guess Gyatso nor our parents told you."
"My...my parents never visited me." Aang says.
Yinyang makes a fake sad look, as if to tease him. "Aww...you poor little baby...As if I should care!"
Aang gets angry hearing that, but then gets very drowsy again. Aang falls into another slumber. After a short moment, Aang wakes up in his dreams again. He notices he's in the Eastern Air Temple, and the whole temple is burning. Aang sees he's standing on one of the temples, then he looks down to see the past Yinyang is fighting the Fire Nation.
"After I was told you were the avatar. I was upset." Yinyang says. "All my life, I wanted to be the Avatar, I always knew I was destined to be the avatar." Aang sees the Past Yinyang blasting and bending powerful airbending at the Fire nation, fighting back hard, even at the ultimate flames of the Firebenders power of Sozins Comet. "While you were hiding in safety like a coward, I fight hard against the Fire Nation during Sozins comet. I was winning at first, but then I became overwhelming.
The past Yinyang airbends a high jump, heading towards the coward of Firebenders. As she falls closer, she exhales a powerful blast of air. Knocking the coward within ten yards of the blast.
The past Yinyang collapses on her knees in exhaustion. "But. It's not my fault I disappeared! I just ran away cause of...cause of..."
"Because the Monks took you away from Gyatso?" Yinyang asks. Aang was surprised to hear that. "I know everything about you, 'Avatar' Aang. I learned a lot about you from within your dreams."
Aang was confused to hear that, but then he starts to get very drowsy then falls asleep. In another moment, Aang wakes up, still in his dreams. Aang notices he's flying, sort of, he's actually raiding a flying bison. He know's it isn't Appa, but a different bison.
"Take a look." Yinyang says, pointing over the horizon. Aang stands next to her, then he sees the past Yinyang, flying with her glider into the storm. "The night the fire nation invaded my home, I barely escaped with my live. I decided to fly off to find you, so I can get what's rightfully mine." Sudden, a storm approaches, The past Yinyang tries to dodge the storm, but then lightning strikes her. "I was stroke by lightning. I barely survived, but was drifted into the sea." The past Yinyang falls into the water, causing a big splash. "I didn't die, but the next thing I knew, I was in the Realm of Dreams."
"How did you end up in the Realm of Dreams?" Aang asks.
"That, I do not know. It's as if the bottom of the ocean was a portal to another world." Yinyang says. "I've waited over a hundred years for you to return, to finally become the avatar...And now, Aang. It's time for you to pay your debt."
Aang is scared hearing that. Just then, he hears a voice. "Aang." It's very fainted, but it does sound familiar, just then, Aang gets very drowsy. The last thing he sees before falling into a slumber is Yinyang's smile.
Later, Aang lays asleep in his room, in his house, on his bed. Aang starts to wake up, then he sits up. Aang looks around, noticing where he is. "Wha...what?" Aang shifts his feet to the ground. "Am I...home? ...What happened?"
Aang stands up, he starts to head downstairs. He looks around to see he really is at home. He then sees Sokka on the couch, and Toph on the other side of the table in front of Sokka. "Hey, guys." Sokka and Toph looks at Aang. "What just happened?"
"Aang! You're awake!" Sokka asks. "How are you feeling?"
"A little drowsy." Aang says, putting a hand on his head. "What happened? The last thing I remembered was being with Yinyang, then...I must have fallen asleep."
"Well, Aang. If you should know, Katara came in, defeated Yinyang and returned you to the physical world." Toph says.
"Really? Katara came for me?" Aang asks.
"That's right." Sokka says. "Oh, by the way, Katara wants to see you. She's out on the hill outside the inner wall of the city."
Aang nods then heads outside. Aang sees the city is still normal, he goes for a walk. Aang can still feeling something a little off. He's not so sure. Aang reaches to the inner wall. He opens his glider and flies over. Aang flies over the land until he finds that cliff Sokka mentioned. Aang lands on the cliff, then he sees Katara from behind sitting on the edge of the cliff.
"Hey...Katara?" Aang asks. Katara turns her head around, facing Aang. Aang is in total shock to see her. She looks so beautiful. She's wearing that old water tribe dress she wore to the dance back in the Ba Sing Se party. Her hair is all around and her lips a little red. "Wow...Katara you...you look...so beautiful."
Katara blushes then giggles. "Why, thank you Aang." Katara gently pats on the ground next to her. "Come sit."
Aang sits next to Katara, and they just watch the sunsetting. "Hey, what happened back in the Realm of Dreams?"
"I saved you." katara says. "Don't worry about it. Let's just sit and watch the sun setting together."
"Together? but...what about the past avatars?" Aang asks, a little nervous.
"Don't worry about them either. Just rest and relax." Katara says.
Aang decides to do what she says, about five minutes later, Aang hears that voice again. "Aang! Don't! ...You've gotten wake up!" The voice was still fainted, but it still does sound familiar.
"What was that?" Aang asks.
"What was what?" Katara asks.
"That...voice." Aang asks.
"I don't hear anything." Katara says.
"I swear...I hear this voice...telling me to wake up." Aang says.
Katara looks at Aang, then puts a hand on his cheek. "You look tired...why don't you sleep?"
Aang suddenly does feel a little tired. "Yeah...I guess you're right."
Katara gently pats on her thigh, then Aang lays his head on her lap. Katara gently strokes Aang on the arm, smiling and humming a song. Aang smiles in his sleep, feeling oh so relaxed.
"Aang...don't!" The voice says.
Aang opens his eyes, hearing that voice again. "I need to go."
"No, no. Stay...sleep." Katara says.
Aang tries to sleep again, then his relaxing returns. Still, he feels something off, and now he struggles to stay asleep. "Aang! Don't do it! It's a trap! Aang!"
The voice became a little louder, but only so slightly. Hearing that sentence made him open his eyes by surprise. He realize's that he's dreaming. "I need to do!"
"No! YOU WILL STAY!" Katara says in an angry, echoing voice.
Just then, everything goes dark. Even Katara vanishes. Aang stands up, feeling quite alarmed at what's happening. "What's going on? Where am I?"
Just then, sinister laughing happens, then lightning strikes. Aang luckily dodges that lightning. He looks up to see a giant face of Azula made entirely out of lightning. Aang becomes scared seeing that. As the Azula lightning opens it mouth and roars, massive lightning spills out of its mouth.
Aang starts to run away at the lightning attempts to strike at him. After that, Aang sees that the lightning stopped. He noticed the Lightning Azula vanished. "What's happening?"
Just then, Sozin does a sinister laugh as his face made out of fire appears. The fire Sozin breaths fire directly at Aang. Aang jumps out of the way then continues running. Except while he's running, he actually falls over a cliff. Aang crashes on the ground, but then quickly gets on his feet. Just then, Aang sees a building. He goes towards it and looks inside through the window. There's a wedding going on. The wedding of Zuko and...Katara. Aang is in total shock to see this, his girlfriend is marrying his firebending teacher and friend.
"Do you, Katara. Take Zuko as you loveful wedded husband?" Iroh asks.
Aang bangs on the window. "No! No! Katara don't!"
"I do." Katara says.
Aang kept banging on the windows, but then his heart breaks at the next sight: Katara and Zuko kissing. Aang stumbles backwards. Just then, he can't control his body, then he forces to kneel. He looks behind him, seeing the Katara he was with on that cliff, only the bottom part of her dress is coated with darkness, so are the front part of her slaves, and the Nightmare insignia is marked directly on her chest. And her eyes are glowing mad red. The Anti-Katara Nightmare.
"You will forever be imprisoned in the Nightmarish Abyss!" The Anti-Katara Nightmare uses her bloodbending to lift Aang off his feet. "You will be forever trapped, facing your worst nightmares!"
Aang grunts painful and struggles to break free from the Anti-Katara Nightmare's bloodbending grip. Just then, the voice speaks, this time, loud and clear. "Aang! You have to wake up! Open your eyes, please!"
He finally recognizes that voice. It's Katara, the real Katara. Aang then closes his eyes, and thinks hard. The Anti-Katara Nightmare waterbeds water on her arm, freezing it all into an icy blade. Just as she was about to stab Aang, he gasps and growls, like she's been stabbed. The Anti-Katara Nightmare drops her bloodbending and Aang falls on his butt. The Anti-Katara Nightmare starts to fade away, then vanishes. The world starts to do the same, then Aang gets sucked back like by some powerful force.