Disclaimer: I don't own Avatar: The Last Airbender. Sadly enough.

Warnings: Character Death, Speculation, Spoilers for the Finale

AN: I admit that I'm a few years late to the party, but at least I beat the movie crowd. This just happened to hit me while I was watching The Swamp the other day.

Time is an illusion. And so is death. But Aang's never really thought of what that means. He misses the monks. He misses Gyatso. He knows that they're dead.

But he wasn't actually there when they died. He wasn't there when the temples fell. He didn't see Kuzon and Bumi age. He just woke up to find everything changed. To find that he's the last Airbender. That Bumi is now an old, old man. That Kuzon has grown up and has his own family and has died just months before Aang could've seen him again. That everything has passed him by.

Time is supposed to be fake. A figment of his imagination. But why can he only go forward? Why can he not wake up back in the temple and hear their laughter? Why can't his new family meet his old one? Why can't he bring Katara and Sokka and all the others and show them Gyatso or Kuzon? Why do things have to change?

Those are the questions he asks himself over the next months and years. As he travels to the Fire Nation. As they gain Zuko and Suki in their little group and then others later on. As they defeat Ozai and start to recover. As life keeps going on around them. Rebuilding the world. Finding and training new Airbenders. Fixing the temples.

But it's not the same. It's never the same. New faces, bright and eager to learn, to embrace their future and a world full of promise. But the old faces are like wisps of shadow. Their voices are echoes that are quieting further with each passing second. He can't even really recall what they sounded like anymore. Can remember Gyatso's words but not the rise and fall of them as he spoke. That he can't quite recall the shade of Kuzon's eyes or if Appa had four siblings or five. That even his own adventures are becoming cloudy as the years pass. That the edges once sharp and clear are now indistinct and hazy in his mind with the press of other and newer memories.

Growing up was hard. Growing older is even worse. And he looks at his friends one day only to realize that they're really and truly adults. That even the Duke has stopped growing. That they're parents with kids of their own and even Toph is a mom. That Zuko's oldest son is nearly an adult himself. Is the same age his dad was when he first started chasing them across the globe.

Time races ever onwards. Races by them until their core group is gathered for their yearly reunion. Only its months earlier than usual because one of them won't make it that long.

And it's hard. The hardest thing he's ever done. Harder than fighting Azula. Harder than trying to learn firebending. Harder than his struggle with himself and knowing he has to kill Ozai but can't do it.

A sky bison is supposed to be a friend for life. For a lifetime. But Aang never realized until this moment that Sister Iio meant Appa's and not his own.

And the only thing he can do is press his face into Appa's furry cheek and just hold on. Aang can only stand there and feel him breathe. Knowing even that will stop soon enough.

Katara is beside him, but she's silent. Unable to find the right words. Sokka is on her other side with Suki just behind him. But they don't say much either. To Aang's left, Zuko just scratches Appa's head in soothing circles with his other arm wrapped around Toph. She has her face buried in white fur, shoulders shaking in time to his dying breaths. Momo clings to her shirt, and the sounds he makes are sad and despondent.

It's never easy to lose a friend. A member of the family. And that's what it feels like. That they're losing something irreplaceable. That he's going where they can't yet follow. And it's not alright. It isn't. It won't be. No matter what they try to tell him.

Appa gives a shudder then. Not much of one. But it's enough.

"It's time, Aang," Katara's voice breaks the quiet.

"No," he denies in return, shaking his head weakly. "It can't be."

But he already knows the truth. Knows it as surely as he knows airbending. And no amount of denial will be able to change that. He's not a child. Not a kid anymore. He's adult enough to admit he's wrong.

"Maybe." He sighs. "Yeah, I know it is." And he holds on that much tighter. "I'm sorry, Appa."

"It's not your fault, Aang," Katara murmurs, tone soft and gentle. "It's no one's fault. This is just part of life."

"He's old, Twinkle Toes," Toph adds, voice muffled from the press of fur. "Old and tired. Aren't you?" she questions and runs her fingers over a horn as long as her arm. "He deserves a rest. Even if it's a permanent one."

Aang can feel his eyes widen. But he's interrupted before he can speak.

"He's a sky bison, not a dragon. They only live so long," Zuko puts in with an unreadable face. "I know it's hard, but it happens."

He turns away then. Clearly thinking about his uncle. About still smiling and happy Iroh who isn't exactly a spring lizard-chicken. Who has problems seeing his pai sho pieces these days. Who leaves the running of his teashop to his assistant Jin more and more with each passing season.

"It's true," Sokka says a minute later. "Hawkie died, too. Most animals don't live as long as Momo. As long as a human." His fingers slow to a gentle stroke across Appa's forehead. "Not that humans live all that long either."

He doesn't have to say it. Doesn't have to remind Aang of his Gran Gran and Pakku. Of their last years together. Doesn't have to remind him of Jeong Jeong either. Or that Bumi might still be around and going strong, but that he isn't invincible. That even he's found a successor in Haru and is now living out his final days in enjoyable retirement, throwing rocks at the youngsters and eating as much jennomite as he can stomach. That he'll be gone someday soon, too.

Time is slipping through Aang's fingers. And even the great and mighty Avatar can't stop it. Can't hold back the rushing tide that's so determined to pull them away one by one. That he's the most powerful bender in the world, to have yet lived, but even this is beyond him. That this enemy can't be beaten by being quick or clever or skilled. That it can't be beaten by him at all.

That he can only accede defeat gracefully. And stroke Appa's fur one more time as he stills completely. As he feels the bright spark that makes Appa himself flicker and float away. As the big and warm body in front of him slowly starts to cool. As Aang can only hang his head and silently wish his friend well on his next journey.

"He's gone."

And it takes him a few seconds to realize that he's one who says it.

"I'm sorry, Aang," Katara whispers, and the tears in her eyes are so obvious.

As clear as the ones in Aang's own. As the ones Sokka freely sheds. That Suki wipes away. Or that Toph and Zuko try to hide. That even little Momo lets dribble down his face and across his graying chin.

And they just stand there for a long minute.

"Have fun on your new adventure," Sokka says then. "In that great sky in theā€¦ well, sky. Goodbye, buddy."

Sokka runs a hand over Appa's head one last time. He's the first to take a slow step back. Suki is next, is there as he turns away and lets out a shaky exhale. Then, Toph and Zuko together. Taking Momo with them as he squeezes her shoulder, and she gives him an affectionate punch to the side. At last, Katara goes, too. Slowly moving back to stand by her brother.

Until only Aang remains. Still holding on. Still not yet ready to stop. Still there as they all come up behind him. As arms and hands wrap around his middle. Not to pull him back but to hold him steady. To be there when he needs them the most. To support him as they always have.

His friends. His family. All of them together. Even the ones he can no longer see. The ones who are departed but not really gone. They're all still here, just out of sight. But not out of mind.

A hand finds his on Appa's fur. He's not sure whose, and really, it doesn't matter in the end. All that matters are the fingers that brush his own. Warm and alive and reminding him that it's time for some things but not for others. That he still has so much more life to live.

And finally, Aang lets go.

Ever Hopeful,