Katara covered her face and let out a long groan as Sokka scrambled up the crane. Zuko started to push himself backward, but Sokka clambered over him to sit between the pair. Katara shrugged while Sokka glowered.

"Didn't have enough to invade that you had to come to a whole new world?" Sokka demanded.

At first surprised, Zuko started to laugh.

"The first time we met, in my world, you threw a boomerang at me," Zuko said. Sokka blinked, his face blank. Zuko continued. "And yeah, I had been invading at the time so I think I deserved it."

Sokka's face soured and he turned to Katara. "And he said we were friends?"

"Hush." Katara said sharply and Sokka rolled his eyes.

"As I just told your sister, I don't know why I'm here. Or even how I got here." Zuko, growing more uncomfortable as these replica eyes stared at him, turned to look down at the ship deck below. "I can't even tell if it's worse or better than what I went through."

Soldiers walked their circuits around the deck and Zuko followed the points of their helmets. He hadn't noticed before the multitude of tiny differences between his world and this one.

Idly, he touched his abdomen again.

"What do you know about this world?" Katara asked, rousing him from his wandering thoughts. Zuko patted his missing scar and faced the other two again.

"Not much. My dead cousin is alive, my missing mother is not missing, and my uncle is the Fire Lord instead of my father. I have no idea if their plan to use Sozin's Comet to obliterate the Earth Kingdom is still relevant, and I don't even know if-"

Zuko stopped as he looked past Katara's head. In the near dark, he could still make out the distant island. He knew where they were headed.

The crumbling structure of the temple rose out of a thick bank of sea fog. It skewered him, and Zuko felt himself reel as he looked at it.

Had he left Aang in the South Pole?

If he had the forethought, perhaps he could have run from the ship when he landed. He could have tried to convince Sokka and Katara, or else picked through the ocean on his own. Another thought came unbidden from somewhere in the depths of his mind.

Aang might not even be out there.

One good reason to call off the siege of Ba Sing Se, and to end the Ice Raids, would be if they had found the Avatar, perfectly preserved in an iceberg.

Zuko felt sick, and suddenly hands were on his shirt, yanking him back.

"What are you doing?" Sokka hissed. "You could die if you fell from this height!"

Shaking his head, Zuko grabbed onto Sokka's wrists, tightening his grip as the other boy struggled.

"Sokka. We have to find the Avatar." Zuko stated with desperate command. "Have you seen any weird icebergs?"

Sokka went from looking frightened to looking angry.

"The Avatar? Icebergs? What are you talking about?" Sokka shoved Zuko off of him and turned to Katara. "I think Spice Prince has a touch of midnight sun madness."

Katara gave him a disagreeable face and then shoved him further back on the platform. Leaning forward, she met Zuko's gaze.

"Our Gran-Gran is from the North Pole and she had grown up hearing about how the Avatar had trained there. He left fifteen years before she was born, but she heard more stories when she was traveling through the Earth Kingdom to the South Pole." Katara explained.

"Aang had been training?" Zuko repeated, his face twisted as he tried to understand. "Then where is he?"

"No one knows," Sokka interjected as he sat back up, pushing Katara back to her corner. "By the time Gran-Gran heard the stories, they were decades old. The Avatar just, disappeared."

Zuko shook his head and slumped over, bracing himself by holding onto the metal frame. Aang had lived, which meant he could also be dead.

"If he's dead, then the next Avatar would be a Waterbender." Zuko said, his voice flat and lifeless.

"Well, it's not me!" Katara replied quickly. Zuko shook his head, but didn't look at her.

"Depending on whether Aang's disappearance was fatal or not, the Avatar would be an adult no older than your grandmother." He said.

"So what?" Sokka asked. "No one seems interested in the Avatar anymore. The Ice Raids are over and your cousin made it seem like they were a bad idea in the first place."

"Then why are we using a warship to take a Waterbender to the North Pole?" Zuko asked.

Sokka's mouth opened, but he said nothing. Katara reached out and grabbed onto the back of her brother's shirt.

"You're bait." Zuko added and looked over at them. "Something bad is going to happen in the North Pole."