I really, really appreciate forgiveness story arcs. And Zutara. So here's this tale. First attempt for this fandom, so please try to not hurt me if you're disappointed.
No rights to Avatar: The Last Airbender
Katara's body coursed with her inborn power, Yon Rha cowering, shriveling beneath her gaze. She'd since forgotten Zuko's presence along with her moral boundaries or the gravity of taking a life. The stilled water created a bubble around her, and in it, no boundaries existed. Nothing, she felt, could stop her from taking this man's life, the man who took her mother's.
Zuko observed quietly from inside the bubble, marveling at Katara's power. It's amazing, he thinks to himself, but the internal compliment laces itself with . . . concern.
Katara drew her hand upward and the bubble's water collected above her head. It hardens and seizes together into sharp daggers of ice.
This is it, Zuko realized. He suddenly noticed he was holding his breath.
Katara propelled her hands outward, and the icy threat rocketed toward Yon Rha. His eyes widened as the ice grew closer, and he finally closed his eyes, bracing himself for impact.
It didn't come.
Yon Rha flinched as warm water fell against him. He opened one eye and dared a peek at his attacker, wondering if she'd shown mercy. Her face communicated that she was just as surprised as he was, but considerably more angry.
"Wha . . . ?" Katara trailed off. She looked over her shoulder back at Zuko, in case he could offer some sort of explanation. His outstretched hand explained enough.
"Zuko?!" she exclaimed. "What are you doing?!"
"I'm sorry ," he replied honestly, lowering the arm that helped him heat the ice, "but I think you should think this through."
Katara lividly turned to face him. "I have thought this through! Over the years, I've thought of a thousand ways to kill this man."
"That's not what I mean," he shook his head, unfazed by her hostility. "Have you ever killed a person before, Katara?"
"Why does that matter?!"
"Because you don't know what it'll do to you," he told her seriously. "I hunted the Avatar for years, and I was willing to destroy anything that got in my way."
"This is different!" Katara yelled. "This isn't some mindless expedition for my own personal gain. This is for my mother!"
"Your mother is dead, Katara," he reminded her calmly.
Katara's hostility faded for a moment, and then returned with such a greater intensity that this time, Zuko actually flinched. "How dare you talk about her like that?! Do you have any idea what it feels like—"
"To lose a mother?" Zuko cut her off, hostility of his own creeping into his voice. "Funny story, actually."
Katara's anger momentarily faded again, but not for long. With a pointed look at Zuko, she lifted her palms, and some of the descending rain collected into sharp, icy weapons again.
Zuko didn't miss a beat. He raised his arm and clenched his hand into a fist, and the weapons dissolved.
"Katara, I'm only asking you to think about this," he clarified.
She ignored him, taking up her weapons again only to have them fall back to the ground as liquid. She shot Zuko an infuriated look, but his steady gaze didn't falter.
"I only want you to consider how this will affect you," Zuko tried to explain.
"Closure," she answered hotly. "That's how it will affect me."
"Then you don't understand how revenge works."
"I thought you were on my side about this!" she roared.
"I'm not asking you to change your mind!" Zuko retorted. "I'm asking you to consider the—augh!"
His body clenched, and he stopped.
Katara's hand had extended and seized control of Zuko's blood.
"Leave. Me. Alone," she demanded through her teeth.
Zuko's stoic exterior dissipated, and his eyes widened at her, shocked at her power. He'd seen her use it before, but he'd brushed it off, didn't think to treat her differently for it or even acknowledge it.
Now, it was rather prominent in his mind.
Katara's other hand shot out, and Yon Rha, in the process of scuttling away unnoticed, froze, his back arching to a painful angle before he collapsed to the ground.
"Don't. Move," she grimaced. Her blood boiled as she controlled another's, as she assumed power over that which she had no right to.
"Katara, look at yourself!" Zuko pleaded. "Look at what this is doing to you!"
Sweat formed on Katara's knitted brow as she strained to control both of the men at once. Rain beat down on the three of them, locked in their nearly motionless struggle.
"This isn't going to give you closure," Zuko realized as the words left his lips. "Aang is right. This isn't the answer!"
She only strained harder, closing her eyes tightly, trying to block out his words.
"Do you think this honors your mother's memory?" Zuko continued desperately. "Do you think she'd want this?!"
"Shut up!"
Furious, Katara relinquished control of Yon Rha and turned her newly freed hand on Zuko. The subtle twitches in his arms and hands vanished as his freedom was lost more completely. He felt the pressure on his bones as his blood squeezed them. He stayed silent, gazing at Katara, willing her to examine herself. They both struggled against each other, will versus will, determination versus determination. Zuko's body began to ache, the blood not flowing the way it was meant to, but his will persisted.
All at once, Katara realized what she was doing.
Her fingers parted as she released control and Zuko's body heaved forward as the pressure was lifted. He nearly falls to his face in front of Katara, whose lips are parted in horror of herself.
"I'm . . . I'm sorry," she stammered, and Zuko had to strain to hear.
"It's fine," he forgives her dismissively, eyeing over her condition.
"He . . . he took my mother from me," she said to herself.
Zuko's gaze at her was empathetic as he watched her try to justify her actions to herself. He knew it wasn't going to happen. That would only provide her with guilt. Combined with the reawakened grief over her mother . . . Zuko felt compelled to approach her. He wasn't sure why.
Katara's palpable rage had diminished and . . . and she was crying.
Zuko cautiously approached until he stood before her. She wouldn't face him.
"Katara?" he offered hesitantly, raising a hand toward her shoulder. Her own hand flew out toward him, and Zuko caught it by the wrist before it could strike him.
Her crying became more evident, even beneath the rain. Without thinking, she fell into Zuko, her body racked with sobs. Zuko froze, his arms levitating above her, but as her sobs grew in volume and her head rested against his shoulder, he found his response came naturally. His hands rested on the small of her back as she buried her face into the space between his neck and shoulder.
"Hey," he said quietly, "hey, you're okay."
In Zuko's periphery, Yon Rha was scooting away, crawling hesitantly from the pair. As soon as he made eye contact with Zuko, he begins to scuttle faster.
He felt she should know. "Katara," he began, "he's—"
Before he could finish, Katara's knees buckled beneath her and she began to sink to the ground. Zuko tried to keep her upright, but failed to find the proper grip, and he settled for sinking to the ground with her. They knelt in the rain for a while. Neither of them was sure how long. It could have been minutes, or it could have been hours. The grey, rainy sky offers little hint of time progression.
After Katara quieted, Zuko asked, "You okay?"
Katara dragged her sleeve across her face. "I don't know," she replied honestly. "Let's . . . let's go back, I guess."
Zuko nodded in agreement, rising to stand. He held out a hand and guided Katara to her feet.
"For what it's worth," Zuko told her once she stood, "I'm glad you didn't kill him."
Katara nodded distantly.
"I'm sorry."
"It's fine that you bent my blood," he assured her. "I've done worse to you and your friends."
"Not that," she raised his eyes to meet his. "Your mom, I mean. I'm sorry you lost her."
He swallowed painfully. "Yeah," he acknowledged, "you, too."
"And . . ." Katara struggled for words. Her gaze flitted towards and away from him as she thought, but her continuation ended up rather simple, ". . . thanks."
"For what?" Zuko asked.
Katara didn't answer, but Zuko felt like he knew.