"Get down!"
Aang flings himself towards Katara, and the two fall to the ground with a thud. Katara's eyes squeeze shut, and she gasps for air. Aang's body forms a shelter over her own, covering her from the debris and ashes raining down upon them.
Katara takes a chance, lifting up her head and opening her eyes. Above her Aang's brow is furrowed, eyes shut tight, not moving from on top of her, determined that even if he doesn't see the end of it she will.
Katara looks to her left, Sokka is holding Suki and Toph to his chest, rocking back and forth, singing quietly, trying to silence the roar.
Her eyes move to the right, where Zuko is sitting with his spine straight, Mai leaning against his chest, almost as if they were welcoming death.
Now she bows her head again, drips of salty water landing and quickly evaporated off of the cracked ground. She realizes they really won't make it through this. It really is the end.
The red glow illuminates the seven friends now. When Aang opens his eyes, ash fills them. He hears the coughing of the girl beneath him and holds tighter. He strokes her hair, filled with sweat and ash, for the last time. "Don't move," he murmurs into her ear.
He is kneeling next to her when she grabs him, pulls him towards her, kissing him with all the energy she possesses until she dissolves into sobs against his lips. Aang pushes her away, pushes her towards safety as he goes to face it.
Overflowing with lava, the trench won't hold. Aang's eyes and tattoos begin to glow as a pocket of air forms, slowly growing, slowly encasing all of his friends.
He's not sure how long he can hold this. He is slowly using up all of his strength. He is slowly fading. Aang falls. He doesn't know how far, he doesn't know how fast, but one moment he is up in the sky, the next in Katara's arms.
A weak smile, and he follows Katara's eyes as they leave his. Above their heads is a towering ceiling of black rock.
Katara thinks of Aang, curled over her to protect her, and looking up at the magma she realizes something.
Aang is like the umbrella of crusted rock over their heads.