Potions are off. Brews give you effects. Time, wood and ingredients are each scored, so be exact.
How to brew
Cook. Put the exact ingredients in a cauldron with fire, a lit campfire, lava or a magma block under it. Boil for the minutes on the card. A cauldron only cooks while you are nearby, so stay close.
Bottle. Right-click the cauldron with glass bottles.
Distill. Only if the card says so. Run the bottles through a brewing stand that many times. Glowstone dust on top, blaze powder as fuel.
Age. Put the bottles in a barrel of the right wood for the time on the card. Nobody has to watch it: a barrel keeps ageing while you are offline and while no player is nearby. Times are real time. One barrel year is 20 minutes.
Barrels
Two ways to get one.
A plain barrel
A normal Minecraft barrel. Holds 6 bottles. Counts as Oak.
A cask
For more room, or the wood a recipe names. Small: 9 bottles. Big: 27.
Building a cask
Use one kind of wood. Put a sign on the front that says Barrel.
Small cask · 9 bottles · 2 blocks long
Front
21Barrel
Finished
You need
8 stairs, 1 sign
14 stairs, upside-down
24 stairs, the normal way up
+a sign saying Barrel
Big cask · 27 bottles · 4 blocks long
Front
32Barrel1
Finished
You need
16 stairs, 18 planks, 1 fence, 1 sign
1corner stairs upside-down, planks between
2planks, with the middle two left empty
3corner stairs the normal way up, planks between
+a fence, then the sign on top of it
stairs planks fence sign, reading Barrel
Chat says Barrel created. Right-click it to put bottles in.
No message? Check these:
Two kinds of wood.
A stair the wrong way up. Aim at the top of a block to place it.
The sign or fence touching other wood.
Stars and mistakes
Every drink gets 1 to 5 stars for how closely you followed the recipe. More stars, stronger effect.
Difficulty sets how much room for error you have, from Forgiving to Master.
Two mistakes ruin a batch for good: a missing ingredient, or distilling a drink that needs none (or not distilling one that does). You get a Ruined Brew. Nothing fixes it.
Everything else only costs stars: wrong wood, a barrel opened late, a cauldron a minute off.
Drunkenness fades on its own. Bread and milk speed it up.
Run /brew seal before selling. Unsealed bottles do not stack. See Shops.
The drinks
Easiest first, poisons last. Each card gives the ingredients, the steps in order, and the effect of a good batch.
DisguiseMade well: looks exactly like Pale Nectar of Myr. Made badly: Cloudy Green Nectar. Almost right: Bitter Green Nectar. Both of those names give it away.