A/N: So, while I was watching the episode the idea just struck me and I couldn't resist... Please tell me what you think. I know this is a small chapter but it is just a prologue, so I wanted to describe the whole idea of the story... Anyway, hope you like it and please excuse any grammar, vocab. etc mistakes... Oh! And this is my first TMNT fanfic so be tolerant...

P.S. The title comes from the greek word "μετάλλαξη" (metallaxi) which means mutation... Yes, I'm greek...

Disclaimer: I don't own TMNT

Metallaxis

prologue:

April's POV:

There I was… Hanging above a huge canister of mutagen, the only thing holding me was an almost broken rope. And I was a big fool to think that Donnie would have been able to catch me.

The rope broke. Gravity must hate me a lot. It started pulling me down, into the enormous pile of ooze. Donatello rushed to me, he jumped. He was so close. He only managed to touch me before I fell. Last thing I knew was I was sinking in the green liquid with an unbearable pain starting to fill every inch of my body. I had never felt so much pain in my life.

I almost run out of breath and with the little courage I had left I swum to the top and jumped out of the liquid. I couldn't see or hear anything. I only felt the pain that had grown a lot bigger in the last few moments. And then it stopped.

I started recalling my senses. When I finally opened my eyes I met with five very familiar stares. Everyone was staring at me with awe and confusion. I caught a glimpse of the figure of the now mutated Baxter Stockman lying on the ground. I tried standing up with trembling knees and I felt the five pairs of eyes following my every movement. It was the time to wonder what was it that had captured their gazes, what had I become?

The first to speak was the questioning voice of the purple-masked turtle. "April?" he said my name not changing the look on his face.

"What is it Donnie?" I still couldn't but wonder what was going on with me. And then, I looked at my hands. They were all green, only three large fingers. My feet were green as well, my whole body was a light green color, and my skin had a texture I had come to know very well in the last few months, or was it years? I had lost counting…

I started freaking out. I spread my gaze all over my body. All I managed to see was green skin, and a large shell. At least I finally knew what was so stunning about my current appearance.

"Am I..?" was all I could spout. I was left speechless, completely freaked out.

"Yes. You must have become like us because I was the last creature you came in contact with before falling in the mutagen…" Donnie started babbling as he always did, when it came to matters of science.

"But it can't be… I can't be… No offense to you guys… It's just… impossible…" I still couldn't believe what I had turned into. Of course I had gotten used to huge mutant turtles but I had never expected that I could be one. It was a lot to take in…

"No offense taken April, losing your humanity isn't a simple thing regardless to what you turn into…" Leo spoke with his comforting and understanding voice.

"So that means we have a new sister!" Mikey shouted with excitement! That boy's light mood just couldn't be spoiled.

"No you stupid! She doesn't have any relation to us, she's just become a mutant turtle!" Raph shouted to his little brother.

"I don't care. She is like a new sister to me." He answered but the conversation didn't continue.

"I guess we should be heading home" Donnie suggested and everyone agreed.

They all started to leave. Four turtles and a poor Casey who hadn't spoken a single word. And then there was me. I just followed my friends without knowing my luck or how complicated things could become for me…