Some magical drugs
(The system I am making these for is probably some GLOGhack, but they can be easily adapted to other systems. I assume that getting the first level requires 100 GP and a skilled labourer's daily pay is 5 SP). I am planning on using them in my upcoming Magical Industrial Revolution campaign.
Wizard Crack
Take a grain of occultum and dissolve it in Aqua Regia. Then neutralize it with lye - inject the resulting mixture through your eye, with a long needle that goes straight into your brain.
Effects: Adds 1 MD per dose consumed. Also, causes incredible euphoria (save or become addicted) and feelings of being all-powerful for d4*10 minutes.
Side-effects: After the euphoria runs out, you feel like shit for the next d4 days, and your whole body hurts(disadvantage on all checks). Also, save or get a mutation. Unskilled users (those without medical background) may also accidentally lobotmize (d4 permanent int damage) themselves with the injection (1-in-10 chance each injection).
Cost: 50 GP per dose
Magical Steroids
Crush an Orc's Thyroid, mix it with Giant's blood and the fat of a bear. Leave it to rot for seven days and nights. The seven worms that will arise will contain the potion - for best effect, dissolve each in a bottle of good brandy and drink each in one go.
Effects: For every week of daily use, grants a permanent point of Strength.
Side-effects: Your muscles are visibly wrong - after 2 points gained this way, they are bulging and covered in pulsating veins. If you gain 4 points this method, you are deformed enough to be rejected by polite society. With 6 points gained you stop even looking human. Also, for each week of use save or lose your ability to sire/bear children. If you have already lost it, instead save or lose your ability to make love.
Cost: 25 GP per dose
Sun's Kiss
When the sun is in Zenith, focus its light through quartz, onto a piece of a living ram's horns. Gather the juices that seep out of its mouth afterwards. Place a drop in each eye, then look at a bright source of light to activate it.
Effects: Sun's Kiśs concentrates sun's power, letting the user see hidden things, as well as in the dark. The user also feels a stronger connection with their surroundings, lightening both positive and negative sensations. The effects last until the user comes in contact with moonlight, tells a lie or falls asleep, whichever comes sooner.
Side-effects: User's eyes slightly glow (revealing their position if in total darkness) and they get disadvantage on all saves against emotion-inducing effects. Slightly addictive - habitual users lose the ability to see in dim light and feel much (thus gaining nothing from carousing) without the drug.
Cost: 10 GP per dose.
Magus's Hashish
Grow hemp in an area where great magics were once worked. Then, make it into hashish using oils blessed by 3 different priests. It is taken by burning it in the hearth of your home (or a campfire if you don't have one) and inhaling the smoke.
Effects: Fills the user with a sense of peace, while warding them against hostile magics. All unwanted magical effects aimed against the user have a 20% chance of failure - same with attacks made by otherworldly creatures. Effects last for 3 hours.
Side-effects: The sense of peace, while pleasant, also makes the user reluctant to do anything hard. Especially start violence (save if you want to start a conflict with anyone/thing)
Cost: 10 GP per dose
Shotpowder
Take black powder and dissolve it in a ration of alcohol inside a soldier's waterskin, from which he drinked his last drink. Set it ablaze, and collect only the dust that remains. Works when loaded into your gun, from the moment it is fired.
Effects: Focuses the shooter's mind and eyesight, granting them a +2 bonus to hit with ranged weapons. Also, it makes it impossible to surprise the user. The effects last until another bullet is fired from the gun that fired it, or the user loses blood.
Side-effects: Makes the user hyper-vigilant, stopping them from falling asleep and making them jumpy.
Cost: 25 GP per dose.
Flier
Preserve the body of a flying bird in salt, then toss the body from a place so high you are closer to clouds than to the earth. Return to the salt, where a leathery egg will be laid, from which nothing will hatch. Best enjoyed in an omlette.
Effects: The user feels light as a feather, with any worries taken away. Their body does in fact become light, allowing them to soar like a bird. The effect remains for as long as the winds do not sharply change their direction (in which case the user slowly gains weight again) or the user witnesses a great artrocity (in which case they fall).
Side-effects: The user cares not for their surroundings while under the influence, as everything feels ephemeral. They get surprised more often (probably on 1 and 2 on the surpirse die, depending on the mechanic you use).
Cost: 20 GP per dose.