Welcome to another Binding of Isaac fanfic! As mentioned in the summary, this fanfic contains spoilers for one of the characters in the game. If you do not wish to be spoiled, read at your own risk.

I do not own Binding of Isaac, and please see Author's Notes for more details.

Other than that, enjoy!

Warning

I didn't know what my name was, or how I came into existence.

However, I knew I had a purpose.

I was to serve as a warning, for what the boy could become.

That boy…

Somehow, I knew his name…

Isaac…

Yes, someone named Isaac had to come along…

Only then could I deliver my warning…

And so I lay in the cold, dark, chest, patiently waiting.

Finally, I heard footsteps approach.

A boy, who I assumed was Isaac, opened the chest.

I finally had the chance to move.

However, he moved first.

Isaac's eyes widened and he recoiled.

For some reason, he forced the chest open wider.

Yet he quickly realized that was a mistake, and a scream exited from his mouth.

I sat up, noting that my limbs were strangely stiff.

I glanced straight at the boy, Isaac. In another second, I put on the biggest smile I could.

If I could make a good impression, perhaps…

But there was no finishing that thought.

Another deafening scream pierced the air. Isaac threw his hands up to the side of his face. His mouth hung open, but any sound had long since abandoned him.

Any chance for giving a warning was lost as Isaac skittered away.

Now, I was left alone, trying to comprehend what happened.

I couldn't figure out any place to go, and judging by Isaac's reaction, it would probably be best to stay away from others.

So instead I looked down, at myself.

For the first time, I noticed my body was blue.

Why would someone's body be blue?

There was only one way to find out…

I had to take a look at myself…

I climbed as far end of the chest as I dared, finding a dusty mirror.

The stiffness plagued my limbs again as I moved.

Why was I so stiff? What had I done to myself?

What made Isaac run away?

If I glanced at my reflection, maybe then I would find my answer…

Cautiously, I stared in the mirror.

A pair of eyes stared back at me.

My own.

No, they weren't eyes.

They were cold, dead, things, that wouldn't even blink when I commanded them to.

My limbs were still stiff as ever, and the mirror put that stiffness on display.

Now, a blue body glanced back at me, exactly same as what I'd seen when I looked down at myself.

The awkward eyes… The blue body… The stiff limbs... But that would mean…

I stared at the mirror for a minute or so longer. Slowly, I pieced everything together.

If I could've, I would've shuddered.

For at last, I understood the details of the warning I was meant to give.

And I understood exactly why Isaac run away.

Was it something he truly wanted? To be like me?

To exist only as a soul, devoid of life's pleasures?

Well, Isaac's life hadn't exactly been pleasant… But to deny himself the chance of it ever getting better? Was that the route he wanted to take?

And the pictures! Oh, the pictures!

They held many memories for Isaac, ones he wanted to erase. And so, he intended to lock himself away.

But he would see them again, maybe even forever…

Yes, just like I did now.

Was Isaac truly prepared for that?

And the demons! Those demons that scared Isaac so much!

The demons that he thought himself to be.

Was Isaac prepared to truly become one, if someone found out what he did?

Would he be willing to never do so and never look back?

Because that's what I had done, living in the shadows of those devils.

It felt like their power was the strongest in the world. Even the toughest enemies were no match for it.

And yet, there were days I wished I could go back.

Still, Isaac wanted to become like me.

But was he ready for the sacrifices it would take?

Was he going set himself on that path, despite the warning he'd been given?

The questions were not to be taken lightly, but I received my answer within minutes.

Isaac staggered back into the room. He glanced around wildly, locking eyes with me as I stared back at him.

The boy broke into a run, hands lunging for the chest.

Isaac almost fell as he caught the handle, but his grip remained firm.

In one swift motion, he slammed the chest shut. The piercing sound rattled the entire area, so loud that I almost missed hearing a panting Isaac walking away.

Several minutes passed, and then there was only silence.

I was in the darkness, alone again.

And yet, I smiled.

I still didn't know what my name was, or how I came into existence.

And yet I knew my purpose had been served, my warning heeded.

Author's notes:

-So I decide to write this piece in order to do a character study on the unnamed charecter otherwise known as Blue Baby. Blue Baby is interesting in that he actually comes from another game made by the same creator, and has no religious references. He also plays a major part in the story in all versions of the game.

-Blue Baby is supposed to be a baby, yet I chose to make him think and act like an adult here because a baby would be very difficult to write. There's no indication that he's a normal baby either, because that he can fight and move around like all the other characters do.

-I chose to use Blue Baby as a warning to Isaac because of his original appearance. In the cut scene where he is unlocked, Isaac sees Blue Baby, the latter smiles at him, and the former is appropriately terrified. It's never stated why he's terrified, but one theory was that he sees Blue Baby as something he could become. That theory has since been debunked, but I took that idea and ran with it.

-The fact that Blue Baby knows Isaac has to do with his true identity. It's revealed late in the game that Blue Baby and Isaac are the same person, with the latter being the postmortem version of the former. While this fic treats them as separate entities, I thought it would make sense for them to know each other based on the connection.

-The fact that Blue Baby isn't self-aware has to do with his appearance. In the game, he just appears in the chest, with no explanation as to why he is there and how he got there. Therefore, I feel like he would be unlikely to know anything about himself if he just randomly appeared like that.

-The idea of existing only as a soul has to do with the way Blue Baby handles health. In the game, Blue Baby can gain health like a regular character, but can only do so through items called Soul Hearts. Almost anything that uses a character's health to determine whether not it is effective treats him as having zero health. This also leads to some other interesting effects.

-For example, two items known as the Polaroid and Negative always work on Blue Baby because the game thinks he has no health. The items are both pictures, which is why there is a reference to pictures and the story. There's another item that turns your character into a devil in exchange for giving buffs his status when health is low. Since Blue Baby is treated as though he has no health, the item is always in effect. Hence the reference to devils.