Zuko didn't open his eyes when he first awoke. He was still exhausted from eight days of escape and seven sleepless nights. He just wanted to relax, remember where he was, and enjoy the feel of the sun on his closed eyelids and the breeze in his hair.
However, the loud discussion going on not five feet from him made this difficult.
"What if we were to infuse it with earth?" said Iroh.
"Can't. The fire would burn it away or the water would turn it into mud." This speaker was a girl, but her voice was much higher than Katara's.
"Hmmmm… Perhaps if it had a center of earth surrounded by wood-"
" Wouldn't that stop working once the wood burned away?" That was Katara.
"Oh! What about metal? We could coat it in that, since nobody can bend metal."
"The fire would melt it."
"Not if the water could cool it!"
He opened his eyes a crack to see his uncle sitting cross-legged in front of him, stroking his beard in thought. He was sipping tea (naturally) as he looked at Sokka, considering the boy's idea.
"That might work, but only if there was both a waterbender and a firebender playing, and they would have to exchange the ball periodically, which would limit their strategic options and put them at a disadvantage to earth- and airbenders." He turned around to look for something in his pack and saw Zuko's open eye. "Nephew, you're awake," he said, smiling broadly. "How did you sleep?"
"What are you talking about?"
"Oh, the avatar and his friends were telling me about a fascinating game that airbenders used to play, and we're trying to adapt it so that members of all four nations can play. Do you have any ideas?" Zuko's only response was a snort of derision. "Ah, well. You are still tired. Hungry, too." A loud growl of Zuko's stomach answered the implied question. "As we are well out of Azula's reach, how about some breakfast?" Sighing, Zuko gave a terse nod. He was far too hungry to argue. "Excellent. There is some fish left over from the last time we landed. It's already cooked, but you can warm it up again."
He wordlessly grabbed the proffered meal and, lighting a tiny spark in one hand, held the fish over the flame until it was warm. As he ate, Iroh resumed the discussion, and he found himself learning the rules of this game in spite of himself. The debate over ball material continued for a few minutes, then Iroh had another idea.
"What about the playing surface? If we abandon the poles, it could be played on the ground, which would allow the earthbenders to move it."
"Oh, like that kicking game we saw in that village!"
"Right."
Zuko involuntarily pricked his ears up as Aang, who was steering, shouted over his shoulder. "That sounds good, but isn't that getting away from the original idea of the game?"
"I suppose so, but wouldn't it be worth it to be able to play with everyone?"
"Yeah, but it'd be nice to have something of the original game in there. Something that needed one of the lighter kinds of bending."
"You could divide the playing field, with poles at both ends and earth in the middle." Everyone turned to look at Zuko in surprise. He didn't look at them as he continued. "Then you could score by building a ramp or kicking with earthbending or shooting it through with one of the other kinds."
There was silence for a good thirty seconds, and then Aang spoke up.
"That's perfect! Let's try it out as soon as we land!"