Time is an illusion and so is death. That's easy for you to accept isn't it?. Someone who's lived so many times." Mu said. He'd hoped to toy with Aang a little longer, but his cordial demeanor had melted away; it was replaced by one of caution and inquisition.
Aang opened his mouth to speak only to be knocked to the ground. He knew the wind. He knew it first and best. Whatever his opponent had attacked him with was hardly the same thing. The boy had changed it- warped it into a colorless potent poison that filled his ears with harsh whispers and all else with distortion and pain.
"You can hear them," Mu stated just above a whisper. He strode calmly towards his target and threw himself into a spin, smiling just a little when the air that resulted struck Aang once again. Every arrow was aglow now, "You can hear..us," he said. There was no distance between them anymore. The light of the moon would reveal that. For once and only once the Avatar resided in his shadow.
Aang tried and failed to stand, hindered by the violent crushing pressure that saturated his limbs and and made a convulsing mess of his surroundings. The whispers were clearer now. They'd become voices—voices he knew- voices filled with terror and agony.
"Time, Separation, Death; are these things an illusion,Aang?"
Aang winced as his eyes filled with light and recognition. In an instant he left his body behind. In this world he was no longer crouched and motionless beneath a starlit sky but standing in the hewn and hallowed halls of the Air Temple he once called home. There was never much in the stark little space that was his room. Still, the frantically penned letter he'd left was impossible to forget. Even now, he could smell the rain that threatened to pour from the clouds.
"Didn't you leave because they planned to separate you from Gyatso?" Mu questioned knowingly. The look on The Avatar's face was a sad and solemn one but he didn't answer. "Didn't the Fire Nation kill him in the time you spent away?" Mu continued. He sighed and leaned against the doorway,"Or maybe his life meant nothing to someone who lived thousands already."
"You don't know what you're talking about." Aang declared .It was the first time Mu remembered seeing him visibly angry, "On top of that, you talk way too much."
"You're right. This is pointless. I'm someone you don't even remember. Someone who doesn't matter to you at all." Mu remarked with a shrug. The smile that followed was brief and sinister. "But I know someone who does."
In the blink of an eye, Aang's foe disappeared. Only now was he beginning to realize his enemy's plan and it left his stomach in knots, "Katara." He stepped towards the door of the little room intending to fling it open. It was the pain that stopped him. With every touch, he felt the sensation of flame burning his hands. He heard high pitched screams that the walls had absorbed in his absence. He was trapped- trapped in a world where even for the Avatar, bending was an impossibility.