Potions are consumables that grants an entity an effect. A player can brew potions using a Brewing Stand or obtain them as items through various other game mechanics.

Custom Potions

Adding a potion follows a similar path as adding an item. You will create an instance of your potion and register it by calling BrewingRecipeRegistry.registerPotionRecipe.

INFO

When Fabric API is present, BrewingRecipeRegistry.registerPotionRecipe is made accessible through an Access Widener.

Creating the Potion

Let's start by declaring a field to store your Potion instance. We will be directly using the initializer class to hold this.

public static final Potion TATER_POTION =
		Registry.register(
				Registries.POTION,
				new Identifier("example-mod", "tater"),
				new Potion(
						new StatusEffectInstance(
								ExampleModEffects.TATER_EFFECT,
								3600,
								0)));

We pass an instance of StatusEffectInstance, which takes 3 parameters:

• StatusEffect type - An effect. We use our custom effect here. Alternatively you can access vanilla effects through net.minecraft.entity.effect.StatusEffects.
• int duration - Duration of the effect in game ticks.
• int amplifier - An amplifier for the effect. For example, Haste II would have an amplifier of 1.

INFO

To create your own effect, please see the Effects guide.

Registering the Potion

In our initializer, we call BrewingRecipeRegistry.registerPotionRecipe.

BrewingRecipeRegistry.registerPotionRecipe(Potions.WATER, Items.POTATO, TATER_POTION);

registerPotionRecipe takes 3 parameters:

• Potion input - The starting potion. Usually this can be a Water Bottle or an Awkward Potion.
• Item item - The item which is the main ingredient of the potion.
• Potion output - The resultant potion.

If you use Fabric API, the mixin invoker is not necessary and a direct call to BrewingRecipeRegistry.registerPotionRecipe can be done.

The full example:

public class ExampleModPotions implements ModInitializer {
	public static final Potion TATER_POTION =
			Registry.register(
					Registries.POTION,
					new Identifier("example-mod", "tater"),
					new Potion(
							new StatusEffectInstance(
									ExampleModEffects.TATER_EFFECT,
									3600,
									0)));

	@Override
	public void onInitialize() {
		BrewingRecipeRegistry.registerPotionRecipe(Potions.WATER, Items.POTATO, TATER_POTION);

		// Use the mixin invoker if you are not using Fabric API
		// BrewingRecipeRegistryInvoker.invokeRegisterPotionRecipe(Potions.WATER, Items.POTATO, TATER_POTION);
	}
}

Once registered, you can brew a Tater potion using a potato.

Registering Potions Using an Ingredient

With the help of Fabric API, it's possible to register a potion using an Ingredient instead of an Item using net.fabricmc.fabric.api.registry.FabricBrewingRecipeRegistry.

Registering the Potion Without Fabric API

Without Fabric API, BrewingRecipeRegistry.registerPotionRecipe will be private. In order to access this method, use the following mixin invoker or use an Access Widener.

@Mixin(BrewingRecipeRegistry.class)
public interface BrewingRecipeRegistryInvoker {
	@Invoker("registerPotionRecipe")
	static void invokeRegisterPotionRecipe(Potion input, Item item, Potion output) {
		throw new AssertionError();
	}
}