No matter how stupid it is, you can't think of anything else to do but keep running. Until you think of a better plan, at least. I'm a prisoner of my own mind.

Dark. That's it! You have to think of light. Maybe that will defeat him. Think happy thoughts.
Markiplier's dog; Chica. The way she jumps up at you and gives you kisses every time you see her. She practically pays more attention to you than Mark does.
Candles; a symbol of light that sometimes give of lovely scents like cinnamon or pumpkin. It can also be put in pumpkins on Halloween>
Darkiplier groans in frustration. "Stop it. Whatever you're doing-stop it!" He booms.
It's working!
Your favourite colour. The way there are elements of it in your room, your clothes and maybe your hair.
Fireworks; especially the bright greens, reds and blues that make you think of Christmas and your friends and family.
Bubbles that glisten in the sunshine.
The sun itself!
The moon and the beautiful stars that brighten up the night because darkness can never be alone.

Darkiplier's screams and yells encircle you, and a sudden bright light attacks your sight. Then the wails come to an abrupt stop. In fact, there's only silence. You open your eyes, and you're awake and back in your home. Everything is back to normal-even the fridge! Maybe it was just a strange nightmare. Maybe you were imagining it all along.

An eerie cackles thunders about your mind. "Don't think you got rid of me that easily."

You drop to your knees in fear and frustration. This...shadow won't just kill you, but he will torment you before. And he'll enjoy it. He isn't just a man in a suit with perfect hair who tells you beautiful lies. He's a gorgeous monster.
"Argh, just kill me now!" You shout in anguish. It only takes a few seconds for you to process what exactly you just said, when Darkiplier replies with
"I can help you with that."