The churning earth spat out Katara and she lashed her water whip out at the first figure she saw. Stone cuffs snared her wrists with a gesture. She twitched her fingers and arced her arms without loss of momentum, and the water spiraled back around and whipped the figure again, who stood unfazed and unimpressed. They made another gesture that stretched the stone over her hands like a giant mitten.

As she started to conjure some strategy of bending with her elbows, another pair of stone hands grabbed and pinned her arms to her sides. The spline of water splattered on the hard floor. Katara shouted in frustration and kicked back at her captor's shin, then shouted in pained surprise as her foot connected with a solid, leg-shaped column of stone.

Her eyes adjusting to the dim lighting of the darkened room, Katara saw these people weren't just earthbenders, but the hybridized humanoid elementals the Twilights liked to turn benders into. The one she'd whipped wasn't even scratched, just a bit damp on their stony skin.

That one turned and walked away with hands folded behind their back, while the second one, still holding Katara by the arms, lifted her just off the floor and marched in lockstep after. She glowered and growled, trying to keep up the air of frustration, because if that left her all she'd have to replace it was fear. But fear had no place here.

As she was carried at arm's length down the stone passageway, she quickly reviewed the situation. Her friends all got separated by earthbenders, and Toph was probably already kicking their butts, especially if they tried the old 'use metal handcuffs' trick on her.

Katara didn't have time to keep thinking or planning. The rough tunnel opened up into a large cubic chamber filled to the brim with cultist paraphernalia. The air was stale and oily, reminding her of raw fish. And smoky, too. There were scorch marks everywhere, along with those elementium bindings shaped like spines and ribs. This was where all the benders like Azula had 'ascended'.

A section of wall slid open on the other side of the room, and another of the green-robed stone men came in carrying Toph like Katara was being carried. Katara called out, and then sucked in a breath as she saw Toph's head loll, the girl limp in the captor's hold. She couldn't be -

Toph's chest moved slowly, and Katara let out her own held breath. Good, Toph was alive, just knocked out. Probably the only way to manage her.

Another stone man marched in, and then a last figure limped in after, this one not made of stone. A woman in a hooded black robe. She tossed her hood back with a grin.

"You!" Katara said.

High Priestess Azil gave a low, sandy-sounding chuckle. "Yes, me, still alive. This is what happens when you fail to check your foe has truly fallen."

"But how?! Toph knocked you off a cliff!"

"I certainly did not come away unscathed. But why would you assume that a priestess capable of increasing gravity could not also reverse it? Don't feel too ashamed. You are far from the first to underestimate the Twilight Hammer's power."

Katara said nothing, instead scanning the room for anything bendable. Surrounded on all sides by earth and metal, and of course Toph had to be unconscious. There wasn't even a plant or a soup cauldron like so long ago when the orcs first captured her. It was all dry down here, except for the three mortal humans, but whatever sweat worked up in combat wasn't enough to fight off four earth-men and Azil.

Where were the others? They'd burst through the door any moment now, right? Someone on Katara's side had to be winning somewhere, hatching a plan, a rescue operation. They better hurry it up, because she was seriously out of options.

Azil ordered the stone men to drop their captives. Toph groaned as she hit the floor, but her chance to move was short-lived, as the next moment Azil conjured a whorl of violet shadows that picked up Toph and enclosed her in a bubble. She woke after a few seconds, groaning about her head, and then panicked.

"Hey – what's going on? Where am I, who's there?!" Toph shouted, grasping around at the interior of the bubble.

"Do you remember me, little earthbender?" Azil said.

"You!"

"That's what your friend said, too."

"Which friend?!" Toph said.

"It's me, Toph!" Katara said. "Hurry, we're surrounded by earth! Everything's stone here!"

Toph made several palm thrusts and kicks. Not even a pebble stirred. Azil laughed.

"You think I'd let you wake up without defenses in place?" the priestess said. "Do not worry. Soon you shall both have full command of your powers again, that and more. You shall be the first metalbender and waterbender to serve us."

"You thought Aang and Azula would be great pets too, and you couldn't keep a leash on either of them!" Toph said. "You're an idiot if you think you can control me. Just ask anybody."

"I'm not serving you either," Katara said. "I don't care what kind of magic you use. The only people really on your side are the ones who want to be already, and you know there's no way we'd ever obey you."

"I knew you would say that. And again, you have underestimated the Twilight's Hammer," Azil said. "Many try to resist. You will serve or face the consequences."

"You mean death?" Katara said grimly, pulling herself up to stand straight, chin raised. "We've put our lives on the line again and again. You're no different than everyone else who threatened to kill us."

"Perhaps not. But putting your own lives on the line is one thing. If either of you fail to obey, I will punish the other instead." Azil grinned like a rictus grimace. "And death will be the last mercy you find from me."

"Don't do it, Katara," Toph said, but her voice quavered. "I've been through worse!"

"Have you really?" Azil said. "I could crush each bone in turn. I could take your feet and hands you rely on so much."

"I'd be a pretty useless minion without any feet or hands." Toph couldn't hide the increased fear in her voice.

And she was right – losing her senses or bending like that wouldn't help anyone, would it? They could try to resist and get tortured, broken, end up useless for the battles ahead.

"I am not giving you a grace period to mull things over," Azil said. "You will decide now, Katara, whether or not to submit. And if you do not, you will decide how long to listen to your friend scream."

They didn't have time to wait for rescue. They didn't have any guarantee a rescue would come.

"I'll do it," Katara said. "I'll become one of... them."

"What?!" Toph gasped. "No! Are you crazy?!"

Azil smiled like an animal and levitated over a set of elementium bindings. Katara stood stoically, staring down the high priestess without fear. The stone mitten flew away to rejoin the earthbender it came from. The metal bindings replaced them, a runed bracer clasping to each wrist. She shivered at the intense cold of the metal, unnaturally chilled like ice cut fresh from a glacier.

Another curled around her neck; she refused to let herself flinch. The metal vertebrae set itself against her spine like a serpent, metal ribs clenching in to hug her own, like a skeletal fist squeezing her torso.

She took a long, shuddering breath, hands curling at her sides. She'd resist obeisance. She'd let this ritual warp her, but she'd never submit to the High Priestess. Katara would use the new power to fight back, just like Azula had.

At least Katara hoped she could. She didn't know what it'd do to her mind. She'd resist. She had to.

Azil chanted and Toph shouted. A wind grew around Katara, or she thought there was a wind, but saw none. She only heard it, a breathing breeze, a whispering that grazed the edges of her perception. The chill spread deeper into her skin, her bones, her blood. She could feel every vessel acutely like rivers and tributaries, her organs like lakes and icebergs. She shivered and fought the urge to hug herself for warmth.

Just like the prison ship, just like the gambling racket, just victory masquerading as temporary defeat.

Toph stopped shouting, and Azil kept chanting, but the sound drowned under the whispering, the roaring. The cold reached the core of every part and limb of Katara and then seemed to invert, double-back, the blood and fluids stretching out to touch the underside of her skin, boiling and roiling, like a storm brewed in her heart and bubbled out to her fingertips. Waves of hot and cold rushed through her, freezing and boiling in turn, like tides coming and going, like moons were blooming and sinking in seconds. She felt each jolt pass through her more clearly, as if she could see the inside of her own body, white-hot threads of ice outlining her jaw and face, forked tongues of lightning into the backs of her eyeballs.

Katara shut her eyes and ground her jaw tightly, fighting to stand up straight as the pain shot through her, each pulse a stronger wave. She could hear her blood pumping, and it seemed to multiply until she realized she could hear all their blood, like the hearts of Toph and Azil were right there in Katara's palms, squeezing and squelching on her skin.

Her senses expanded through the room, feeling the moisture of the air, each drop of blood and sweat and saliva, all their organs, their bones and marrow, the softly pulsing tides of life that cycled through them like each person was a planet and sea all their own.

Behind her shut eyes she saw squirming lights, something foreign and slimy, undulating outside of space and sense. The elementium pulled it closer like a ship pulling in to moor, anchored Katara's being to a deep and oil-slicked ocean just on the other side of her eyes, something vaster and darker than the night sky which she only just now could see.

It whispered. Bilious thoughts spilled through her mind like the wet coiled innards of a disemboweled animal. She flinched and found she couldn't move at all, not even to open her eyes again. She stood frozen, as the dark space of her eyelids expanded out to close around her, snaring and holding her rigid.

One eye and then several shone out at her like lanterns, lighthouses on an endless coastline, stars in a midnight sky. The sky threatened to fall if the pillars kept breaking. If they couldn't hold up the sky the stars could crush and consume them, a dozen, hundred, million hungry lights, white needles clawing for traction on the fabric of the veil, worms rising through soft loam after rainfall, they came through one at a time and needed a million, needed the door open, the earth split, the sky torn in half, the glaciers melted, the poles conjoined, let them in, submit and let them see, let them know –

"No!"

Katara wrenched away. The vision sucked at her brain like swamp mud, hating to relinquish a new prize. Her eyes fought to finally open.

Azil gazed over her appraisingly. Katara gazed over herself. Her fallow skin faded to frosty blue-white at the hands, a pale glow that extended up to the elbows in her veins. She no longer felt cold, nor hot, but buoyant and fluid, at one with the flow of energy in the room, the chi of water and life. In a way she didn't feel real, or maybe just un-solid, like she floated in a lake, like she could swim through the air itself. Was this how Yue felt becoming the moon?

"See the gifts the Masters can bestow?" Azil said.

"Yes." Katara seized the High Priestess with a wave and flung her across the room.

Did she just bloodbend? During the day?

Azil stumbled up from the base of the wall where she'd landed, unsteady as she favored one leg. "Stop! You will not raise your hand to me again!"

Katara's hands were already poised, but the bracers stabbed her with cold pain, shook her skull with it. Azil's will resounded through the runes. Katara struggled to attack her, swinging and striking at air, until relenting at last. She could win that battle later. Azil's attention would wane eventually. She couldn't hold back the river forever.

But as the moment of fury itself passed, fresh guilt hit Katara. She'd promised herself never to bloodbend again, for neither rage nor revenge. Nothing was worth that, was it? Controlling someone against their will – but that's exactly what Azil did to her, and had done to so many others.

Azil floated over another set of bindings, moving in on Toph, whose head turned quickly toward every sound. Katara snarled impotently. She tried to move, but some unspoken order held her in place entirely.

The walls rumbled. The four earth ascendants turned at once toward the door. Azil turned a moment later, letting the elementium bindings clang on the floor. Katara twitched, still fighting for any weakness in Azil's control. The High Priestess glared at her, and the rumbling grew closer. Katara twitched again. The energy bubble holding Toph flickered.

Katara grinned now. "You can't keep this up. You're holding the wolf-bat by the ears."

"Your triumph will be taken before your eyes, when I command you to destroy your own friends," Azil said.

"You're having trouble just keeping from destroying you. You might have survived the last fight, but you didn't really regain your strength, did you?"

"You – insolent girl," Azil sneered. "You know nothing of my strength! Your petulance only ensures your future despair!"

Toph spoke up. "Ugh, can't you Twilight crazies talk like a normal person for one minute? You're so dramatic, it's like I'm fighting those characters in the fight club again!"

"Silence!"

"Or more like they're putting on a bad play," Katara said.

"Yeah, who needs The Ember Island Players when we can listen to these guys?" Toph laughed.

Azil's glare snapped from one to the other. It was hard to tell if she was snarling or smiling. They looked about the same on her.

"I will visit upon you such pain you will eat your words! You were unwise to test the limits of my mercy, and now that I have bound your waterbender, I have no reason left not to harm you! I've been waiting for the day to exact my revenge on you for the bones of mine you broke!"

Azil raised her hands. The energy bubble darkened until going opaque, and then shrank. Toph yelled in alarm, her voice muffled behind the swirling shadows.

Then the door slammed open and chaos erupted.

Zuko, Sokka, Suki, and the Kyoshi Warriors burst into the room. The earth ascendants leaped to attack. The floor and walls broke and swung wildly as bursts of flame shot past each opening. The warriors split to surround and converge on Azil on Sokka's shouted orders. Azil shouted her own orders.

"Kill them! KILL THEM!"

Katara fought – she fought her friends, she fought the order, this way and that, she struck against both sides, hardly knowing her own movements. She didn't just bend water, she became water, she shot and slid across the room like a tidal wave, to and fro. She lashed out at Sokka and pulled her strikes at the last minute, bruising and cutting but not killing. Then she'd turn and lash at Azil just the same, before the priestess' will took over again. Back and forth, back and forth, she felt split in half, the room was a blur, the fight turned to indistinct shapes and noises.

Something heavy knocked the breath out of her and pinned her against a floor. The bracers burned. Her spine was on fire. She screamed and struggled.

"Katara! Stop, it's me! Calm down!"

The voice was Suki's. Katara squeezed her eyes shut and opened them again. Her brain was shivering, burning, Azil's orders compelling her to strike, driving her mad and dizzy.

The room was quiet. The rumbling had stopped. Suki had Katara pinned to the floor. The others stood around her, looking down in worry. The runes ringing down into her bones wanted her to kill them. She wanted to kill them. She closed her eyes again, hoping that if she couldn't see them, it wouldn't be so hard to resist. She could still sense them, crimson and pulsing.

"Toph, hurry!" Sokka shouted.

Katara jerked on reflex to try to strike at his voice. She gave a cry of guilt and stopped, then a cry of pain as the bindings punished her resistance.

Several hands held her down as Toph's recognizably tiny hands pried away the elementium. The pain slipped away. There was a pressure she hadn't noticed, a squeezing on her heart, that relented the moment she became unbound. She let out a long, ragged sigh of relief.

"She's not turning back," Sokka said. "Why isn't she turning back?"

Katara opened her eyes again. The pain and dizziness were gone, but nothing else changed. She hadn't just put on a costume, hadn't dipped her hands in blue make-up to wash it off again. She'd reached a new paradigm. She could feel the permanence of her new self.

"I'm like this now," Katara said. "I'm... whatever this is. Whatever I am."

"Is it safe to let you go?" Suki asked.

"Yes. I'm not going to hurt any of you now."

Suki moved off her, and Katara stood with surprising ease. Still buoyant. She looked around the room. The earth ascendants were shattered to pieces. Azil was dead, lying in her own blood. Katara stared and tentatively reached out with her newfound senses, confirming that the priestess' heart was motionless.

Katara looked over the others, seeing their injuries. "I'm so sorry – I couldn't stop it, her magic was too strong -"

"Katara, it's okay," Sokka said. "We're just glad you're safe."

Alive, but not human. She'd have to deal with this later.

"So what's the plan now?" she asked.

Zuko spoke up. "Benedictus, the 'Twilight Father', is still at large somewhere in the city. I just escaped from him and found the others in the city prison. Those stone men were the Dai Li, and there are more of them."

"A lot more," Sokka agreed. "At least one or two for each of us, plus all the ones that were with Benedictus. That's just the ones we know about. But they won't get the advantage of surprise again, now that we know they're here, and we know about this bunker. We need to move ahead with the original plan, which is to get the rest of our forces up here to retake the city. That'll give us a defensible position to operate from. After that, we need to find out where the rest of the Twilight bases are, and rally all our possible allies on this world. There's probably a lot of intel in the palace that'll give us leads on that."

Katara smiled faintly. "Have I mentioned how great it is to have such a good planner for a brother?"

"Yes, but I won't complain if you mention it again," Sokka said with a returning grin.

Zuko interjected with his usual grimness, "They conquered the South Pole. They're tapping into a source of energy there."

Katara's brow creased. "I... saw something when Azil changed me. A vision. Something... dark, and powerful. It wants something at the poles. A way in."

Suki's expression hardened with recognition. Her jaw tightened but she said nothing.

"Then we can retake the South Pole next," Sokka said. "For now, we have to take Caldera City."