(This is a short fic based on a picture I saw on tumblr which is here( tumblr user moriar-tea post/6415057388/i-had-a-terrible-dream) . I hope you enjoy)

You open your eyes, blinking away the bleariness. Everything around you seemed to be glowing and you rub at your eyes. This must be Prospit, you've sure heard a lot about it from Terezi.
As you are looking around, a shadow falls over you and you look up.
"Wha-?" you start, shock covering your features. 'That's… Jack', you think, recognition hitting you,' but why does he look like that?' He growls at you, and your eyes fall to his blood covered sword.
You watch in horror as he lifts it up and you cringe back, then nothing.

You open your eyes again, back in your normal attire and there's nothing around you. It's a blank slate. Crossing your arms you let out a breath that puffs out. Why is it so cold?

You start to walk around, looking everywhere but there's absolutely nothing. You feel your body getting colder as you continue to move and you sharp teeth begin to clatter.
As you walk, you look down at your shoes, since that's the only thing changing besides your body temperature. Suddenly there's a bright dot on your shoe.
"What's that?" You grumble to yourself and lean down looking at it. Your eyes widen as you recognize it as your blood color and you hear another drop, looking over to see Terezi's color splattered on the ground. You stand back up quickly, holding out your hands as sprinkles of color start to rain down.

Horrified as a particularly big drop hits your hand, you wipe it frantically on your sweater, trying to clean it off but it just seems to blossom across you chest and grow. You look back down at your hands but they are still covered in a rainbow of blood. The torrents of blood come harder and faster and you frantically try to back up. The blank slate was better than this. So much better.
You feel heat meeting your eyes as you're overwhelmed but as you back up the drops of blood lessen and stop. You look down, seeing that there was still blood on your hands. You look past your hands to observe that you are standing in a pool of your own blood.
You swing your head around to spot where the blood had come from and look down, seeing two bodies. Your eyes widen as you realize that's you and Terezi, dead on the ground. "Why?" you ask no one quietly, terror shading your expression, you're heart plummeting. You slowly reach out a hand like that can help them—help you in some way. You feel the heat that had been brimming in your eyes slowly spill out and run down your cheeks.
As you take a shaky step forward, shadows fall across the two bodies and you look up. There stand all your friends, splattered in their own blood, dead eyes staring at you. You gasp, and jump back as though you've been physically shocked. As you do, you sneaker slips on the bright red liquid and you fall back, struggling to regain your balance.
Just when you've about regained balance, you feel a cold hand wrap around yours, jerking you backward. For a moment, you're too shocked to fight against it, but as soon as one grabs your ankle, you try to escape the cold tendrils. But no matter how much you try, they over power you, more and more keep grabbing at you, snaking around your body.
You look back at them as they pull you backward and it's a void, cold and dark. As you look back forward you see they've pulled you off the edge of a cliff. Just as you scream the darkness completely engulfs you.

Then nothing.

You wake with a start, a tear running down your face. You suck in a deep shuddery breath as you realize it was a dream. Well your dream self getting killed was a dream that was real but the horrible image of all your friends dead was just a dream.
You stay there for a moment before you remember you had fallen asleep at the edge of the main room. You sit up shakily and wipe at your face quickly, glad that no one was close enough to see anything. To them it'd appear your were just rubbing sleep out of your eyes.
You had to warn the other's not to sleep. You didn't want your friends experiencing the awful dreams that you just had.
You stand up slowly and start to make your way over to Terezi. As you do, you look around and everyone appears fine, going about their normal business.
You're so glad they're ok. That she's ok.