IMPORTANT NOTICE; PLEASE READ: This story is meant to have a mystery vibe to it, and should leave the reader with questions at certain points. If you feel confused about something, don't worry. It's most likely intentional. Every major plot point or issue will be explained in the story, or in the Explanations/Clarifications section at the bottom of each chapter. If you are still confused on something, feel free to leave a comment and I will attempt to clarify! Thank you, and enjoy!

DISCLAIMER: I DO NOT OWN [Prototype], A Certain Magical Index, OR A Certain Scientific Railgun! THEY EACH BELONG TO THEIR RESPECTIVE OWNERS!

Chapter 1

Don't talk to Strangers

It was a clear, calm night in Academy City, Four thugs strolled along the empty sidewalk, throwing crude jokes as they continued their walk along the usually empty sidewalk. Today however, the sidewalk had one unwelcome visitor.

One of the men looked up just in time no notice a lone figure calmly walking toward them. The figure, hands in pockets, seemed ignorant to the thugs' presence. The thug smiled, knowing that in a city like this, they were bound to run into a rich boy once in a while. Perhaps today would be the lucky day.

"Hey fellas, take a look at this."

Three heads snapped up in attention, focusing on the approaching figure. Three smiles followed soon after.

With fluid movements, the four quickly produced their signature weapons. Three of them pulled out small, electrically charged knives, while the fourth, a young lad, close to 16, formed a small ball of fire in the palm of his hand. He quickly extinguished it, concealing his esper powers from the stranger.

Now that he was closer, the four could make out details. He seemed to be a teenager, wearing brown boots and blue jeans, with a thick, unzipped black vest, that covered a thin grey sweatshirt. The hood was pulled back, revealing a young, pale face, and short, messy silver hair. The most prominent features however were the eyes. They were a cold grey color, which could best be described as…disturbing.

"A bit late to be walking around alone, huh, lad?"

The pale teen said nothing and continued on. The man who spoke up frowned. He refused to be ignored. Especially by some teenager. He reached out with his left hand and grabbed the teen by his right shoulder.

"Don't ignore your betters, boy. You know, I was thinking of just taking whatever money you have and walking away, but your attitude is giving me second thoughts about the whole letting you go part," said the thug.

Still no response from the teen. The man narrowed his eyes. His patience with this brat was wearing thin.

"Didn't anyone tell you to respect your elders, you little brat? When a man talks to you, you respond. When a man with a knife talks to you, you get on your knees, and you hand over whatever the hell he asks for."

Slowly, the teens raised his head, and the man found himself staring into a pair of eyes that shouldn't belong to a teenage boy. He saw these types of eyes in cold-blooded killers. However, before he could rethink his actions, the teenager spoke.

"I try to make a habit out of not talking to my food."

If he had time, the man would have been surprised at the depth of the voice. However, before he could register what was going on, he felt excruciating pain shoot through his stomach. He looked down, attempting to find the source of the feeling, only to see the hand of the teen embedded in his stomach.

The other three thugs barely had time to gasp, before tentacles erupted from the teen's chest, engulfing their wounded comrade, and seemingly absorbing him into the teen. The spectacle was accompanied by the grotesque sound of bones breaking, flesh being torn, and the wet groans of their partner.

They took several steps back, attempting to scream, but unable to find their voices. One moment, the leader of their little gang was threatening the teen, and the next he was just...gone.

As soon as the man was absorbed, his silver-haired killer looked up at the three remaining men. They could now clearly see an insatiable hunger in his eyes. It was the look of a wild predator.

The teen smiled as he took a step forward. The smile held no warmth, no compassion, no happiness. It was the smile of a killer who had cornered his prey, and was about to make the kill.

He took another step forward, and another, and another. All the while, the remaining backed away, their jaws opening and closing, attempting to formulate words, but failing miserably. Eventually, one of them tripped.

That was the trigger.

The thugs regained some composure, and began shouting and cursing at the teen.

A few seconds passed, then, realizing that shouting would do little good, the three quickly turned around, attempting to put as much distance between them, and the thing as possible. As they ran, the teen behind them continued to smile. A hopeless attempt at escape was one of the reactions he favored most. It was almost as good as futile resistance. Almost.

With a leap that no living creature could have possibly matched, he launched himself into the air, landing a few feet in front of his prey, blocking their path.

With his back turned to them, the three thugs could clearly see a red tribal symbol on the back of his vest that resembled a pair of wings. It also seemed to give of a faint red glow,

Without warning, black spikes erupted from the teen's back, quickly impaling two of the three remaining men. Tentacles that seemed to materialize from the spikes engulfed and began absorbing the two writhing men. Within a few seconds, the squirming tentacles retracted, leaving no evidence that the two thugs ever existed. The spikes also retracted into the teen's back. The clothing on his back seemed to bubble and squirm around until it had assumed its original shape.

The last remaining thug, a teenage esper with the ability to control fire, stumbled backwards, attempting to hold down his dinner. As he stumbled backwards, the silver-haired teen slowly turned toward him. The ruthless smile on his face was gone, replaced by an emotionless glare, which probably could have intimidated any living Level 5 esper.

The fire-based esper quickly raised his hand. "I-i-if you take one more step, I-I-I'll call the police," he said, raising his phone up to his ear.

The silver-haired teenager cocked his head to the side, a ghost of a smile appeared on his face.

"That's fine. Nobody will get that call though."

The fire esper blinked in surprise. "Wh-what?" he stammered. "Why not?"

Suddenly, the standing teen just vanished. No 'poof', no noise, nothing. He just vanished. Then, without warning, the esper felt a cold grip around his neck.

"Because dead men can't talk."

The esper didn't have time to scream.

Explanations/Clarifications

The Espers: So if you haven't seen A Certain Magical Index or A Certain Scientific Railgun, then you probably don't know what espers are. Espers are basically people who have been given special powers that are grounded in science (not magical, spiritual, etc.). These espers are not unlike the Conduits from inFAMOUS, inFAMOUS 2, and inFAMOUS Second Son. These espers only exist in Academy City as far as I know.

The Reactions: The reason I didn't have any of the thugs use their weapons or abilities is because I wanted to show how utterly shocked they were. When one is in a state of severe shock, they tend to do things without thinking. For example, if you had a knife, and something from your worst nightmare walks up to you, you'll probably be in shock for some time before you realize you have a weapon. Also, people don't attack something when they believe it will lead to their imminent death. The thugs didn't attack because they didn't think they were a match for our lovely OC here. Obviously, they weren't XD.

The Tribal Symbol: If you have trouble picturing the symbol on the teen's (his name will be revealed later, just so you all know) back, it's the same symbol as on Alex Mercer's back.

(A/N) So this is the first chapter of the crossover, and I hope you enjoyed it! Feel free to leave suggestions, constructive criticism, or your thoughts about my work. It is always appreciated . Also, at the end of every chapter, if there is something that I feel might need to be more clearly explained, I will have an Explanations/Clarifications sections down at the bottom of the chapter. This is Anti-Atom signing of. Laters!