"After them!" Zuko shouted, voice oddly cool, gestured for the now mostly standing Dai Li to follow the waterbender who was escaping with his prey. They looked to Azula, who paused absently, eyes on her brother's face. He couldn't believe she wasn't going after them, until he remembered she didn't know. "The girl's a healer, and she has some spirit water from the North. He isn't dead, Azula."

She frowned at that and gestured to her Dai Li. Most launched themselves up on pillars of earth and were gone within seconds, giving chase. Then she turned back to face her brother with a strangely happy smirk. "Azula...?" His sister was acting far too calm. The Avatar was getting away, why didn't she-

Azula waved off his concern with barely two fingers, nothing else, and he calmed down. That was her 'I know what I'm doing/I know more than you/I'll explain later, dum-dum' signal. From back when they were getting in and out of trouble together as children. Back when they were almost friends. So he bit his lip, inhaled a little deeper, and turned around.

Zuko looked back at his uncle, and regretted it.

He couldn't decide which was worse; watching the Avatar slip through his fingers again, the fact that his uncle was the reason for the escape, or the way Iroh didn't defend himself afterwards. As if the Avatar escaping was the only important thing left.

As the Dai Li encased the former general in even more rock without opposition, Zuko couldn't hold back any more. "Why, uncle?" His voice almost cracked.

Iroh turned his head and looked away, lips pressed tight in grim mockery of his once open smile. Red hot anger and betrayal raged inside him, but they now fought more than self control. A new side had emerged, bringing with it ice to soothe and numb. Zuko almost sighed in relief. The rage and pain was still there, just... buried behind ice. Not burning him inside out; for now at least.

He watched one of the remaining Dai Li agents knock Iroh out cold with a less than precise blow, uncharacteristically angry, and surprised himself by not caring at all. Azula gave some orders, smooth and in control as usual, and Iroh was dragged away to be locked up. Another small gesture and the remaining earthbenders followed after, determined not to let the general escape again. It was just the two of them now.

They studied each other's faces with little emotion for a moment, neither one relaxing their guard. Then Azula smiled and stretched her arms. He recognised the movements; standard cool down exercises following a brief, everyday exercise. It made him smile, a little. Typical Azula.

"So," she began with more warmth than he was used to, "little Zuzu is good for something after all. Had to happen sooner or later, you are related to me, so of course some of my greatness spilled over." He chuckled a little, smiling that bit wider. "Father will be proud of us, Zuko. Capturing Ba Sing Se and defeating the Avatar. And capturing the traitor."

Zuko lost his small smile at that. "Uncle..." He started but was utterly unsure of what he meant to say. Wasn't a traitor? He'd just demonstrated exactly where his loyalties lay. After all this time, after overhearing it and confronting him this same day, though it felt like a lifetime ago... And now to have him actually stand in his way and defend the Avatar against him...

"Betrayed you, Zuko. He betrayed you, and our entire nation. But let's not talk about traitors for now. I must say I am impressed that you can call on the blue flames. How long have to been able to?"

He was about to answer since the start of the battle, then stopped. He remembered his fight against Jet, that sense of cool fury and the thin trails of blue fire he had accidentally called upon with his blades.

"Once, maybe, several weeks ago, but only a little. This was the first time I really noticed." It felt incredibly weird to be just talking like this, knowing the Avatar was being chased above them. He raised a palm and watched the blue spring to life, still slightly awed.

"Beautiful, isn't it?" She whispered from his side. He hadn't even noticed her move, too caught up in the dancing flame that was so familiar and yet so different; so much more. He nodded. She called up her own next to his, palms almost touching, and they watched them swirl together over and over.

"Only lightning is more beautiful, and powerful of course." He was suddenly struck by an idea. He started moving away and called back to her. "I want to test something." She quirked a curious eyebrow and watched him centre himself some distance away.

"Shoot lightning at me."

She was stunned. "What? Why?" But then she remembered how uncle the traitor had somehow commandeered her blast and sent it away. She nodded, cutting him off before he could start, and took her stance. His funeral.

He watched her circular motions, they were slower than before as if to let her better observe what he was doing, and prepared himself. The pure energy arced towards him ridiculously fast, but somehow his eyes took in each glorious strand that twisted as if searching for him. His fingertips raised by themselves, hours of practice made it pure instinct, and he felt a rush like never before as the lightning entered and flowed within him. In, down... It was amazing. Pure energy coursed through him and he held it for the moment, exhilarated beyond belief. He was almost tempted to try and keep it there, but he knew it would kill him with absolute certainty. This was pure power and it was too much. He raised his other hand, pointed off to the side of the cavern, and felt it fly. Up, out!

It leapt from his fingertips with even more power than it had arrived; his own energy adding to make it even more deadly. He realised with some amazement exactly how little control he had over it; he was its guide, nothing more. Once it left he could spread its focus but that was it.

Zuko sighed as if he had been holding his breath, which he might have been doing. Funny how lightning, the most powerful firebending technique, had nothing to do with breath. He straightened and looked to his sister. Ahh, so worth the risk! He would treasure her expression for the rest of his life. Absolute shock was spread over her face as if written in bright red. He closed the distance between them and considered how he himself felt about this.

He felt more alive than ever before, and absolutely confident. Wielding that much power, power from outside himself, bending it to his will and growing it with his own energy before casting it wherever he wished... It was awesome. He couldn't imagine anything headier. But it also humbled him. One slip would bring instant death. It was beyond his control; no matter how much he bent it, it was going somewhere fast and all he could do was point it away.

A deep breath filled him completely and he stood taller than ever. The anger and pain were still there but they had been blown apart by this. It felt like the lightning had seared it away, leaving small scattered ashes where once they had raged.

Azula finally pulled herself together and softly applauded, impressed. "Very clever. You will teach me this new form, later. Now, we have a wall to bring down."