In the Attack on Titan world?

Chapter 28- protecting the wall

It wasn't enough. I wouldn't be able to this fast enough!
Rocks were beginning to fall behind me. I focused hard and felt the warmth spread through my body like lightning. The ice formed quicker. Soon we were encased in an ice like pocket. I could still feel the rumblings but as if they were distant.
"Layla-" I heard Eren say.
I pointed up, clenching my hand to a fist and breaking through part of the ice, leading to the exit they had come from. Levi took my hint and began to zip up there, taking Historia with him. Hanje was being cradled by Connie who zipped up after them. They were soon followed by Sasha, Mikasa and Armin. Jean waited.
"Detransform so I can take you." He said.
I concentrated and burst through the nape this time, pulling myself free from the body, beginning to steam and break apart. Jean grabbed me and we zipped up after the others.
I felt like I had no strength left, so eagerly let Jean carry me. What met us was a huge crater. Reiss had clearly left the cavern. And he had crawled away, already at a fair distance.
"Quick." Levi said. "We have to catch up with him."
"He's headed for the wall." Armin said.
Hastily we all jumped onto horses or into the cart respectively. Myself, Eren, Hanje, Levi and Armin were in the cart,   which sped after the newly formed Titan.
I couldn't stop the pain in my chest.
It hurt.
Why? Why did it hurt?

"Ah." I said clutching my heart. "It burns."
"Layla!" Eren said grabbing me. I gritted my teeth. Then I saw my arm.
Reiss had injected me at some point-how? It didn't make sense. There was a clear needle mark in my arm. One that hadn't been there to draw blood previously.
"I'm alright Eren." I said through gritted teeth. "Just tired."
Levi just gave me a look. Hanje was out for the count and Armin was too busy looking to Reiss.
He was moving pretty quick for a Titan that couldn't lift his head and crawled. Steam rose up from around him, and he was creating a deep trench as he went.
The cart was soon picking up speed but we couldn't get too close. The heat would have been unbearable.
Then I had a thought. We couldn't as humans. But as a Titan?
"I need to transform again." I said still through gritted teeth. "I can get closer than we can here."
"But Layla-your exhausted, surely-"
"I need to. Once I'm there I'll stop him. And wait for you all to arrive." I just looked at Levi.
He was our commanding officer-he would be the one to say yes or no.
He just nodded. "If we don't stop him now, the wall will be breached and their are homes and villages the other side.
I nodded.
This time I didn't want to slice my hand, so I did an Eren and bit down hard enough leaping from the cart on my hand.
Light overwhelmed me and I met the ground with my Titan feet and sprinted off towards Reiss.

With the others.

"She's going to hurt herself." Eren said, his eyes wide. "She's already tired."
"But she's fighting." Levi said. "Your just as tired brat, and she trusts us to look after her."
Eren looked at his sister. His brave sister, who not only had been shamed, something he could never imagine, but kept going. Fighting. He was glad and proud she was a part of his family.

With Layla.
I panted. Breaths being torn from me. The pain was also back too. But I pushed it aside.
Reiss was almost at the wall.
I screamed my Titan scream. Making him stop. It seemed like only a second but he stopped- long enough for me to catch up to him and jump on his back, trying to wrench the skin from his nape with my teeth.
Steam wrestled with my skin, but I carried on. That was when he began to move again. It took all my strength to hold on to him- teeth deep in his neck.

With the others.

"She is amazing." Armin said, Eren nodded. "Look!" He then shouted and they watched Reiss start off again, a Titan Layla still attached by the teeth.
"Oh no." Eren said. "He's going to reach the wall."
To them, it looked like Layla had thought of the that too as she moved, digging her heels into the ground forcing him up.
He had no face, no jaw and looked like the something from nightmares. No socket no eyes. It had been from where he dragged his face along the ground. Steam pouring off him in thick white waves.
"Come on Layla." Eren said. "You have him."

With Layla.
I fought against him. He had power to him and could feel beads of sweat pour from my skin with the effort of halting him in his tracks.
"You will stop." I said, using authority. My voice coming out in a growl.
He stopped.
Had it worked this time.
"You will stop!" I said firmer.
Reiss went loose in my arms, falling to the ground, without a hole in carrying on.
Had I done it?
Cautiously I let go.
In a second he had grabbed me by the neck, and flung me towards the wall, continuing his trek.
I landed, trying to avoid the wall as much as possible, rolling to a stop just at the foot of the wall. Reiss still came towards me.
My heart burned again.
This time. I used it.

I screamed long and loud.

It echoed around me.
Reiss was a mere foot away from me, when he sank to the ground. This time lifeless.
I sat panting. I could feel the burn. Had he grabbed the case when I wasn't looking and injected me on the sly with his daughters power?
It seemed it. I could control him a lot better than I had done previously. Moving slowly I padded towards his body.
An arm shot out aiming for my throat, but I punched it before it got there. Ripping the arm from the socket.

It landed a few feet away. Steam flying from it.

At this point we had to have alerted those on the wall.
I was running out of energy and power. And Reiss seemed to feel that.
He threw another punch my way and this time though it ripped, it didn't rip fully so I did again before he realised.
He was armless now, so no longer moved.
I panted. I was growing lightheaded. I needed to get Reiss out before I lost consciousness. I tore at his nape again with my teeth and pulled him with my steaming hands.
What a coward.
I laid him on the ground, the Titan form beginning to disintegrate. The last thing I saw before blackness overcame me, was the cart pulling up with horses alongside.