Scarecrow: Do you know why I wear these syringes on my hand?
Oracle: Because you’re insane?
Scarecrow: I usually disperse my toxin as an aerosol. It’s efficient. But not pure. Now, the terror I can elicit with a concentrated dose, administered directly into the bloodstream, that is… beautiful to witness. The long-term damage is more severe, of course.
Oracle: Are you done talking?
Scarecrow: I am. But you have barely begun. You’ll be incoherent when my toxin dissolves the wall between your conscious mind and your suppressed, subconscious nightmares. But as those fears slowly recede, they’ll take this pathetic defiance with them.

“Batman: Arkham Knight”