As part of my continuing futile quest to incorporate some element of crafting into a pen and paper rpg, I present some alternative potion brewing rules.
Potions
Potions may be purchased in a town. Their basic purpose is to give players a way to expend long term resources in order to sustain themselves better in a dungeon, and also to allow players to better leverage gold spent into success in the field. Potions may be quaffed as a move action that does not draw attacks of opportunity. They may also be fed to an adjacent unconscious character as a standard action that does not draw an attack of opportunity.
Basic Potions
Cure Light 100gp
This potion cures 10 hp of damage.
Ferocity 150gp
This potion imparts a +1 alchemical bonus to critical threat range for 1d6 rounds.
Courage 200gp
This potion imparts a +2 alchemical bonus to AC and saves for the rest of an encounter.
Experimental Recipes
Any player may spend 300gp to attempt to discover a new potion recipe. In doing so, he picks a basic potion to attempt to modify, spends his gp, and rolls on the following table, with the result being an effect that occurs in addition to that potion's usual effects. That character may then brew that custom potion any time he is in town and has the gp to burn. The recipe is finicky, however, and may not be transmitted to another character. You cannot add additional effects to custom recipes.
Recipe Results (1d20)
(All results are in addition to the basic potion's normal effects)
1-3: Failed recipe.
4: Vim: This potion cures an additional +5 hp. No price change.
5: Vigor: This potion cures an additional +10 hp. +50gp.
6: Regeneration: This potion cures an additional +15 hp on the quaffer's next turn.
7: Fire Protection: The quaffer enjoys +10 fire resist for the rest of the encounter. +50gp.
8: Antitoxin: The quaffer enjoys +10 poison resist for the rest of the encounter. +25gp.
9: Aromatics: The quaffer has any disease or weak conditions cured. +25gp.
10: Strength: The quaffer enjoys a +2 alchemical bonus to damage for the rest of the encounter. +50gp.
11: Fearlessness: Removes fear, and adds +1 alchemical bonus to AC for rest of encounter (stacks with courage). +100gp
12: Haste: Drinker enjoys +2 initiative bonus for rest of the day. +25gp.
13: Survival: Drinker enjoys +10 cold and electric resist for the rest of the encounter. +100gp.
14: Berserk Strength: Drinker enjoys extra +1 critical threat range for rest of encounter. +150gp.
15: Growth: Drinker occupies two spaces, suffers -2 penalty to AC, and enjoys +1 reach for rest of encounter. +200gp.
16: Heavy Curing: This potion cures an additional +20hp. +200gp.
17: Restoration: This potion cures an additional +10hp, and removes any weakness, stun, or blindness. +100gp.
18: Vibrancy: Pemanent +1 bonus to initiative. Only works once per drinker. +100gp.
19: Life: Permanent +1d6 max hp. Only works once per drinker. +300gp.
20: Improvement: Permanent +1 alchemical bonus to a saving throw of drinkers' choice. Only works once per drinker. +300gp.
Option: Limited Recipe Results
If you're into this sort of thing, you could cross off each new potion effect once it has been used, and have players re-roll that result if it comes up again. I don't know what this would add to a game, but it seems pretty hardcore to me!