TW FOR SPOILERS:
Okay so I have the syringe, got it from the dark world with all the roaches. But I don't know what to do with it, I though it go to the mother that tells Randall not to play with sharp things, but no, so I'm kinda lost
SPOILER ANSWER
the syringe is used on the mother in the maze world ! theres a maze world you get to and in the center is a clay house, you can go inside and you use it in there!
theres a blood spot in the black and white world where you found the syringe that takes you to the maze world btw!
also the dumpsters are random in the black and white world, youll need to click on them in order to get to a certain area
SPOILER
So in the Black in white world with or without the roaches? And what is this mother asking for? I know one wants you to light a cig, and the other is telling you not to mess with sharp things, and I thought that's were the syringe would fall into play, but I guess I need to find a knife or smt