Junkie Prophet/Playing With

Basic Trope: A character uses psychoactive substances to induce visions of the future.
 * Straight: Alice prepares a mixture of special herbs, burns them and inhales the smoke before curling up in a ball and Dreaming of Things to Come.
 * Exaggerated: In this universe, even smoking pot will give you intense, lucid visions of the future.
 * Downplayed: Alice's visions require a complicated, pseudo-religious ritual to set off, one aspect of which involves taking a psychoactive substance.
 * Justified: The drugs provide Alice with sufficient Artistic Stimulation to inspire a Eureka Moment.
 * Inverted: Alice is an extremely sensitively attuned psychic, but when she gets stoned it dampens her powers.
 * Subverted: It turns out what Alice thought were visions were just vivid hallucinations.
 * Double Subverted: ...but then the pink elephants she'd assumed were hallucinations suddenly rampage through town.
 * Parodied: Every single time Intoxication Ensues, the intoxicated party comes out with some deep and significant prophecy.
 * Zig Zagged: It's kept ambiguous for as long as possible whether Alice's visions were prophetic or nonsensical, and it's hard to tell either way - some of her prophecies seem to come truer than others, but we don't know what she actually saw first-hand and we don't know whether You Can't Fight Fate is in effect or not.
 * Averted: People do drugs without seeing the future, and/or can see the future without taking drugs.
 * Enforced: "We want to make these people Noble Savages, but we know they did drugs. If we make it look like a religious ritual we can get away with it."
 * Lampshaded: "How come he gets to see the future? When I smoke pot all I got was hungry, giggly and disoriented!"
 * Invoked: A tribal shaman lies about the drugs giving him visions because it allows him to (a) consolidate his position as spiritual leader and (b) get high.
 * Exploited: A tribe tampers with the drugs of a rival tribe's shaman to guarantee terrifying, demoralizing prophecies.
 * Defied: "What, you thought the stuff you saw when you were high would come true? Why on earth would you think that??"
 * Discussed: "He's offering to tell my future. I bet the next thing he does is light up a bowl."
 * Conversed: "These prophets always need to take drugs to see the future. Clearly they're just seeing things."
 * Deconstructed: The prophet gets addicted, first to the ability to see the future, and then to the substance that helps him do so. Everyone else thinks he's just making pathetic excuses to stay on the stuff, and it must have messed his mind up if he really thinks he's psychic. No-one believes this strung-out madman when he warns them what he's seen.
 * Reconstructed: The downsides to his methods are shown in full, but people can't ignore the fact that his visions inevitably come true. He has to wrestle with the fact that his abilities save the lives of others but are ruining his own.
 * Played For Laughs: In a modern high-school reimagining of Macbeth, the three witches are comical stoner stereotypes.

From my trance-state induced by drinking the brew of the holy mushrooms, the way back to Junkie Prophet has been made clear to me!