Catlin heard the distant screaming—ponies on the wall, shaking with terror as forces they knew they could not possibly contain came barreling towards their loved-ones. She'd seen the defenses now, the high walls, the boiling oil and crossbow-wielding soldiers. They had minutes, perhaps, before the enemy breached their gates.
In the room all around her, resistance crumbled. Luna's generals saluted to her, then sprinted off without a word. To command their troops, if they were brave. To cower in the basement, if they were not. They would die just the same.
"Open the cage, Princess," Catlin whispered. Her voice was low, insistent. "I can't stop this without her."
The princess spun on her. She alone had not crumbled and fled at this terrible sight. Past Catlin, chunks of barrier tumbled from the air like huge sheets of glass, dissolving into shimmering light before they hit the ground. Then came the roar—the ground shook as they advanced across the bridge.
"You can stop this?" she whispered. "A naked child?"
Catlin crossed the room, standing beside the cage. "Not just me. Us, together. Open the cage, and let us go to the wall." She didn't wait for a response—Catlin breathed in, letting the power of the Void suffuse her every tissue. Her warframe was still here, attuned to her, waiting for its operator.
She could feel the pony's terror, even if she couldn't put it into words anymore. Guilt and shame consumed her, but neither of those were strong enough to overpower the far more powerful need. The princess doubted her, but the frame didn't. We can do this.
Catlin's human body vanished, and her vision returned within the cage. She stood confidently, gesturing at the lock with one hoof. She didn't doubt this frame had enough strength to tear the cage to metal scraps, if she wanted. But she would need that magic for the enemy outside, she couldn't waste it now.
Princess Luna stopped beside the heavy metal cage, looking down on her. Where she had been nearly Catlin's equal in height, she towered over the frame. There was anger in her face greater than anything her frame had ever imagined. But Catlin knew it, and so she shared her strength.
"I do not want to trust you," she hissed. "You belong in that cage."
Ponies shouted outside, charging into battle. Others screamed and wailed as they died in agony. Catlin heard other voices join them—terrified refugees, cowering in the castle. While their soldiers fought overwhelming numbers, their citizens could do nothing more than wait for death. There was nowhere for them to run.
"Let this be your test, Tenno Catlin. Betray my trust, and I swear to strike you down. Even if it costs my life." Luna lashed out, metal glittering through the air so fast Catlin barely saw it. The front half of the cage fell forward, its joints hissing red. The princess tossed her something, and Catlin reacted—or maybe the frame did.
It was a sword, like the fine weapons wielded by the chamber's guards. Catlin swung it once through the air as though she still had hands, but her motion was not restricted.
"Now, stand beside me," Luna instructed. "Prepare to fall."
Catlin obeyed, then her world warped. She was familiar with teleportation by now, though rare was the frame that could manifest it so directly. She spun once in the air, then righted herself, preparing to drop. She landed on a patch of bare walkway, directly over the gate.
The drawbridge was raised, but the Infested didn't care. Corpses piled in the gap, reaching closer and closer to the wall. The fallen sunk and melted together into a ramp, its tendrils flailing wildly through the air. They lashed out at the wall, striking away chunks of stone.
Ponies fired into the fleshy abomination with their crossbows, without success.
Battle raged around Catlin. All along the wall, creatures fought for their lives. The airborne infested assaulted the wall from above, not caring if their bodies were destroyed as they toppled defenders from the battlements. Any who fell to their wounds would rise again to spread the taint behind the walls.
"Well, Tenno Catlin? This is what you wanted."
She no longer had the ability to reply, not with her words. Her actions would have to do.
Catlin pointed down behind the line, where a handful of winged infested were harrying the troops. Then she gestured to the princess.
The alicorn nodded back. "And you?"
She leapt off the wall, body buzzing with power. For the second time since arriving in this strange place, Catlin and her frame were in perfect alignment. They had one mission, and one will. Her magic sliced through the wall of infested flesh, burning through in a sweeping beam from her horn. It fell to the side, spraying chitin and shattered bones and ichorous blood.
Catlin landed on the stone a second later, raising her sword before her. There were hundreds of infested here, maybe thousands. Every pony too slow to escape to the castle, every poor soul who had succumbed to the infestation—they were here.
She focused her will, lifting dozens of objects from the stone—crossbow bolts, broken weapons, shards of rock, spinning them rapidly in the air in front of her, shredding nearby infested to ribbons. Then she released, blasting out at the crowd with a hundred gunshots.
What I wouldn't give for my Brahma against numbers like these.
She couldn't reach all the way to her orbiter to teleport things from her armory, or this would be a very different fight. But she could teleport. One of the bulky infested charged in her direction, and her frame blinked several meters, just as the princess had done to bring them here. The pony was much too slow to stop, and charged right over the side.
Catlin faced against numbers beyond counting. But these were freshly infected, the weakest they would ever be. She didn't even want to imagine what they would be like if they had a few thousand years to fester in an orokin tower somewhere.
Warframes did not tire, not like people. So long as she had a steady stream of energy harvested from her fallen foes, she could continue to fight, leaving a trail of dead behind her that grew into a barrier of its own.
She could not hope to fight them all. Hours she struggled, with her frame broken and damaged many times—but always reinvigorated from the fallen. How much greater would it be, once she got the chance to install a few critical mods?
Eventually, Catlin raised her sword to find there was no infested nearby to strike down with it. She blinked, staring out at the battlefield all around her.
She had slain thousands, infested bodies toppled off the cliff's edge or rapidly rotting off in a pile. There were so many corpses that there was little room to walk in places, and she had to teleport past some.
It's not enough. She hopped up onto a chunk of fallen building, scanning the area around the castle. The cloud of infested striking the wall was gone.
She felt a surge of relief from the frame, overwhelming joy at what it believed was success after such a painful, grueling battle.
Catlin couldn't lie to it, though. The infested weren't gone, they had just stopped attacking the castle. She could see them below, now that she knew what to look for. They'd fled from the castle, and gathered instead on one of the lower tiers of the city. The buildings were all covered in biofilm, pulsing, vile sores, and waving tentacles. The infestation won't flee to feed elsewhere, not with so much food this close. It was mechanical like that, with needs and a predictable pattern.
Is there enough of it in one place to think?
Something landed on the rock beside her, startling her from her thoughts. She spun, in time to see Princess Luna landing closeby. The drawbridge banged into place, and pony guards made their way down, shoving the infested into the gap to clear the path. Luna herself had an escort in the air around her, crossbows in their forelegs and bat wings holding them in a low guard. "Tenno Catlin. I'm told you held an entire flank of this battle on your own. And yet you live."
The warframe started to bow before Catlin realized what she was doing. She rebelled, separating from the frame in a flash of void-light. While the pony bowed, Catlin appeared on the bare ground beside it, back straight. She covered her chest with one arm, expecting to start shivering with cold—but she didn't.
The ancient Orokin flight suit shifted beneath her, metal and fabric clicking together as she briefly covered her chest. She let her arm back down, eyes widening.
At least the princess didn't attack her this time. Her eyebrows went up. "In all that, you had the time to find something to wear? Were you here to fight, or show off?" She was actually smiling this time, one of the few. The pony soldiers wore expressions of shock and horror, looking out at the fallen with tormented eyes. These creatures were too pure for this—they'd need lots of therapy when this battle was over. Assuming they survived it.
Catlin reached for her helmet, and found the crown melted, just where she'd taken a blow from a Sentient boarder. Her suit was frayed... and there was an amp around her fingers. She twisted the helmet to one side, and it retracted down the back of her breastplate. "I didn't find this during the battle. This is what I was wearing before, when I... died." She flexed her right hand, settling her fingers into the familiar metal frame of her amp. Not that she'd need it. For all the nightmares waiting for her on this peaceful world, the Sentients didn't appear to be one of them.
"They've retreated on all sides, Princess!" a guard yelled. "Looks like all the possessed ponies are going the same direction. We scared them off!"
Not likely. They don't feel fear.
Her frame did. It stood straight, glancing sideways at her. For the first time in her many years of service, Catlin was actually taller than her frame. It slouched low, looking almost shy as it put her between itself and the princess. She no longer scared it, but the princess did.
"I owe you an apology," Luna said. "But I'm afraid there will be no time for that conversation now. We don't know why the enemy has retreated. Above all else, we cannot allow them to depart the city and spread this infestation further."
Catlin took a few steps closer to the princess, lowering her voice to a whisper. She could only hope the soldiers wouldn't overhear. "When the evacuation is over, Princess, I'm afraid you will need to burn this city. Even the biomass of plants and passing animals will eventually be enough to feed the infestation, make it strong again. This city must be destroyed."
"I have considered that," she whispered back. "My sister and I will do so, when the time comes. While we fought, an evacuation has already begun. But Princess Twilight has limited strength, and can only teleport a handful of ponies at a time."
She gestured back at the castle, urgently. "My sister wishes to meet with you. She is still weak from her efforts shielding the castle... it is possible she has advice on how we should proceed with the remaining victims."
Catlin glanced to the side, at the almost pony hiding behind her. "She can come too, right? A Tenno shouldn't be separated from her warframe."
Princess Luna nodded impatiently. "Of course. We will... resolve the moral quandaries of this nightmare after Equestria is safe."