when i think of white powder i think of drugs... hah.. but maybe it is some type of hallucinogen where it makes you see things that aren't really there.. hence; zombies, killer clowns, nurses with messed up faces and knives, ghosts, gargoyles that come alive, nightmares come to life, etc....
when will the rest be posted? and will someone post all the clues together? i feel like im missing a few.