Burnout AU:

The Fire Prince is different than she remembers, barely an echo of himself. He moves as though he's treading deep waters. Sometimes, Katara feels like she's watching him through a fog.

After being exiled from the North for bloodbending an abuser—before facing Zhao and being thrown to the seas for Zuko to find—she'd heard the stories. Prince Zuko died as the Long Night began, caught in the explosion of the Yuurei. And yet, here he was, offering Katara passage to Omashu so she can reunite with her friends.

(Breathing in time with the fires of a ghost ship.)

Reverse AU:

“Years ago, a spirit showed me a reality in which I was meant to be the Avatar,” Zuko's airbending Master said. “Kyoshi died a century earlier and the Tribes didn't join forces to make the world their hunting ground. The Cycle itself was different, too—elemental opposites didn't succeed one another. It was so marvelous, yet so strange. However, this is our reality, and you're the Avatar.”

Placing a tile on the board, Aang continued, “Perhaps if water wasn't the next element in our Cycle you'd get a free pass, but we're not so lucky. Everyone's out to kill you so the next Avatar will be born in the Water Tribes. If that happens, the world is doomed. So you better get this exercise right, Zuko, or Princess Creepy-Yet-Pretty's going to catch you. And this time, I don't think she'll hold back."