"That's what I said."
"But what do you mean, it's not red?"
Sokka jumped up from the couch in the newly-renovated beach house. Zuko lifted his eyebrow at him, turning away from the Pai Sho board in front of him (on which he was losing spectacularly to Toph).
"Is it that surprising?" he asked, bemused.
Sokka waved his arms wildly, prompting Suki to gently steer him away from an expensive vase nearby. "You wear red all the time!" he yelped. "Your clothes are red, your gigantic mansion of a house is all red, there's even red detailing on the Pai Sho tile in your hand!" Zuko glanced at the offending tile before looking back at Sokka, who continued. "How can your favorite color not be red?"
"Sokka, everything's red in the Fire Nation," Aang said, momentarily distracted from his game of tug-of-war with Momo. "Don't you think it'd get boring after a while?"
"And besides, Sokka," Katara interjected, yelling from the adjacent kitchen, "your favorite color isn't blue, but you're always wearing it."
"Only 'cause Snoozles doesn't ever do laundry," Toph snickered, earning an indignant "hey!" from the Water Tribe boy in question as she cackled.
"Look, I'm sure red's a great color," Zuko spoke up over the din as he placed his Pai Sho tile down, "but I really think I would appreciate it more if I could actually see it, you know?"
He said it in such a casual tone that it took a moment for anyone to respond. When his sentence got through to them, they all (excepting Toph) turned and gave him a quizzical stare. He caught their looks and responded with similar confusion. "Wait, did I not tell you guys before now?"
"Tell us what?" Katara asked as she walked into the room and sat on the couch Sokka had left vacant.
"Well, I'm colorblind," he answered simply. "I can't see the color red. Or green, for that matter."
"Woww," Aang said, the fight with Momo now entirely forgotten. "That's crazy! But you can still see other colors?"
"Yep." He pointed at a few objects in the room. "Brown. Orange. Blue," he said, now pointing at Sokka's shirt. "But that could be red or green," he added, now looking at the (red) vase that had just escaped destruction a few minutes prior, "and I wouldn't know."
"Wait, so what is your favorite color, if it's not red?" Sokka asked.
"I like yellow," Zuko replied, and Aang smiled big.
"That's my favorite color too! How come you like it?"
Zuko shrugged, moving his eyes back to the Pai Sho board. "Turtleducks. Candles. Sunflowers." He smirked. "My adoptive kid brother that wrestles with lemurs," he joked, reaching over and tugging lightly on the back of Aang's yellow collar. Aang laughed.
"Count yourself lucky that you can even see that much," Toph said. "I don't even know what color is."
"Well, Toph," Suki started, sitting back onto the couch, "color is... hmm. Well, it's…" She lapsed into silence, stumped on how to explain it.
"Really hard to describe, unfortunately," Katara finished as she sat down beside Zuko.
"I suppose you could try to explain colors with texture and temperature," Zuko mused. He set down another tile. "I don't know how well it would work, but it's worth a try."
"Tell you what, Sparky. If I can win the game with one more move, you have to find every single yellow thing in the house and bring it to me to feel."
"You're on. There's no way you can—"
Toph set down her tile, already laughing maniacally as Zuko sputtered and Katara rubbed his back comfortingly.
"What— what— oh, come on!"
Twenty minutes later, Aang found himself in a pile of bananas, daffodils, and various gold ornaments and accessories (including the Fire Lord headpiece) sitting on the floor, not entirely sure how he ended up there. Toph rubbed the end of his sleeve between her fingers, brow furrowed as she felt the flame-shaped crown with the other hand.
"I'm starting to think that yellow is a very confusing color."
A/N: I've seen lots of 'what if Zuko was partially/completely blind' fics (and good heavens, I love those, it's such an interesting idea), but I don't think I've ever seen one about him (or for that matter, any other character) being colorblind. I mean, we have no way to prove that he isn't, right? And anyway, there's no way an entire nation can have the same favorite color, regardless of them all wearing the same color palette. I had fun writing this, hope you enjoyed it too. :)