Of all the people assaulted by Amon, Katara had asked Lin and Korra to come meet her. She had been healing both of them for some time; Lin because any child of Toph Beifong would get into more scrapes than three ordinary children and Korra so the young waterbender could see how healing worked from the inside as well as the outside. Katara knew other masters were looking into the problem, but few had the direct connection she had with two of the victims.
If any one of the victims had the key, it would be Korra, since she had retained her latent ability to airbend. And, Katara had long accepted that the Avatar often broke the rules.
But Katara asked Lin to see her first. Maybe, for once, it would be simple. "Just lie down and try to relax. Is it too cold for you?"
"It's fine," Lin said. "Just hurry up. Please."
Katara reached for the water she kept for healing, letting it pool around her hands, and sensed the water flowing in Lin's body respond. Toph used to talk about how stone felt to her, and the closest Katara could come to the way the earthbender spoke was healing, feeling the pure water around her hands, the blood flowing through Lin, water suffusing every part of her, and intermingled with that, the energy of Lin's body. In a state like this, Katara had to wonder why no one had ever learned of bloodbending before Hama. Like this, Katara could feel the strength and resilience of the body and spirit, but also how delicate it was, how important it was to train one's healing ability as much as training in combat bending.
She was approaching a century now and she still was marveled by how her element looked and felt in its myriad forms.
Katara let her hands guide their water towards Lin's face, and the younger woman's eyelids fluttered as she felt the coolness. Katara could feel something there, a dark spot in a sense that wasn't vision. Not anything physical - goodness knows, she'd worked on enough tumors and foreign objects to know what those felt like. She hadn't felt anything like this since… since she was a girl, healing Aang after Azula had struck him down under Bah Sing Sei. At the time, she thought it was the scar tissue that she couldn't get rid of; later, Aang had mentioned that one of his chakras had been temporarily blocked by the injury.
But Katara had learned a thing or two since the war. She closed her own eyes and reached for the energy, attempting to guide it to fill the dark spot and rejoin itself without harming Lin.
The spot in Lin's chi flow was like a severed limb; she could sense the ends, but couldn't will the connections to be made. Eventually, she had to give up and returned the water to its jar. Lin opened her eyes at the sound of the splash, and looked up at Katara.
Katara shook her head. "I'm sorry. Give me some time for a cup of tea, then send Korra in."
Lin stood up, stiffly. Katara didn't know if that was disappointment or old injuries. "Do you think you'll have luck with her?"
"I think if anyone can be healed, it will be Korra," Katara answered.
She made her tea, and sipped it. Tonight was the full moon; she had chosen that deliberately for its power, even if she couldn't waterbend during a full moon without thinking about Hama, and what Sokka had told her about what Yakone had called her. That she was a coward for declaring bloodbending a forbidden art. Of course, Katara knew what 'strength' meant to a man like Yakone: the ability to force others to do his bidding by any means necessary. Even Hama's strength was born of fear and anger: the fear and anger she felt towards the Fire Nation for what they'd done to her. Katara had sworn off using her bending to make others afraid of her, and had learned to control her temper.
But, healing under a full moon made her wonder, perhaps, if she had understood how bloodbending worked better, perhaps she could undo its damage. Or at least have seen Amon's technique for what it was before he used it on so many, perhaps even have been able to teach waterbenders a way to block it.
Or perhaps it was just hard for an old master to admit she didn't know everything about waterbending.
Katara swallowed the bitter dregs of her tea, and then went to call Korra in to work on a miracle.