Functions

While loot functions can be used in different ways, from now on the examples on this page will shown with LootEntries but they can easily be used in other places.

addAttributes

Add attribute modifiers to the item. In the callback, you can use multiple functions to add attributes. Probability can be used to have a random chance the attribute will be applied.

If using simple, it will use the default equipment slot for the item.

• .simple(attribute, amount: NumberProvider)_{, see NumberProvider}
• .simple(probability, attribute, amount: NumberProvider)
• .forSlots(attribute, amount: NumberProvider, slots: EquipmentSlot[])
• .forSlots(probability, attribute, amount: NumberProvider, slots: EquipmentSlot[])

Possible attributes for vanilla can be found in the Minecraft Wiki. Also mods may add own attributes, for that you should take a look at the corresponding mod page.

Possible slots are: "mainhand", "offhand", "head", "chest", "legs", "feet".

• Syntax:
  • .addAttributes(callback => {})
  • LootFunction.addAttributes(callback => {})

LootEntry.of("minecraft:potion").addAttributes(attr => {
    attr.simple("generic.max_health", 1)
    attr.simple(0.99, "generic.max_health", 2)
    attr.forSlots("generic.max_health", 3, [SLOT_MAINHAND])
    attr.forSlots(0.99, "generic.max_health", 4, [SLOT_OFFHAND])
})

addPotion

• Syntax:
  • .addPotion(potion)
  • LootFunction.addPotion(potion)

LootEntry.of("minecraft:potion").addPotion("minecraft:poison")

applyBonus

Applies a uniform bonus based on given multiplier. The item count will be increased between 0 and multiplier * enchantmentLevel.
Minecraft uses this for sea_lantern or redstone_ore as an example by applying apply_bonus with uniform_bonus_count as formula.

• Syntax:
  • .applyBonus(enchantment, multiplier: number)
  • LootFunction.applyBonus(enchantment, multiplier: number)

applyOreBonus

Applies a bonus based on special formula Minecraft uses for ore drops:
count * max(1; randomInt(0, enchantmentLevel + 2))

• Syntax:
  • .applyOreBonus(enchantment)
  • LootFunction.applyOreBonus(enchantment)

// In vanilla minecraft often uses fortune here. Of course you can use any enchantment here.
LootEntry.of("minecraft:emerald_ore").applyOreBonus("minecraft:fortune")

applyBinomialDistributionBonus

Applies a bonus based on the binomial distribution, where n = enchantmentLevel + extra and p = probability.

• Syntax:
  • .applyBinomialDistributionBonus(enchantment, p: number, extra: number)
  • LootFunction.applyBinomialDistributionBonus(enchantment, p: number, extra: number)

LootEntry.of("minecraft:emerald_ore").applyBinomialDistributionBonus("minecraft:fortune", 0.2, 3)

applyEnchantmentBonus

Applies a bonus, when player uses a specific enchantment. If no enchantment is provided, "minecraft:looting" is used as default.

• Syntax:
  • .applyEnchantmentBonus(bonus: NumberProvider)_{, see NumberProvider}
  • .applyEnchantmentBonus(enchantment: Enchantment, bonus: NumberProvider)
  • LootFunction.applyEnchantmentBonus(bonus: NumberProvider)
  • LootFunction.applyEnchantmentBonus(enchantment: Enchantment, bonus: NumberProvider)

LootEntry.of("minecraft:emerald_ore").applyEnchantmentBonus([2, 5])

LootEntry.of("minecraft:emerald_ore").applyEnchantmentBonus("minecraft:fortune", [2, 5])

setCount

Info

For LootEntries we often want to change the existing count instead of adding a new one. Because of that using setCount on a loot entry will replace the existing count function if one exists, otherwise it will add it. If you still wish to add multiple count functions you can use .addFunction(LootFunction.setCount(count: NumberProvider))

This behavior does not apply for LootModifiers through LootJS.modifiers() event!

• Syntax:
  • .setCount(count: NumberProvider)_{, see NumberProvider}
  • LootFunction.setCount(count: NumberProvider)

LootEntry.of("minecraft:emerald_ore").setCount(20)

LootEntry.of("minecraft:emerald_ore").setCount([2, 10])

limitCount

Limits the item count between min and max. Min and max both can be optional by using null as value.

• Syntax:
  • .limitCount(min: NumberProvider | null, max: NumberProvider | null)_{, see NumberProvider}
  • LootFunction.limitCount(min: NumberProvider | null, max: NumberProvider | null)

LootEntry.of("minecraft:emerald_ore").limitCount(2, 10)

// Or this. Always have at least 10 but never more than [30, 35]
LootEntry.of("minecraft:emerald_ore").limitCount(10, [30, 35])

setCustomData

Set the custom data tag of the item.

• Syntax:
  • .setCustomData(nbt)

LootEntry.of("minecraft:emerald_ore").setCustomData({ someCustomStuff: true })

setName

• Syntax:
  • .setName(name: Component)
  • LootFunction.setName(name: Component)

LootEntry.of("minecraft:emerald_ore").setName(Component.translatable("item.minecraft.emerald_ore"))

LootEntry.of("minecraft:emerald_ore").setName("Emerald Ore with new name")

enchantRandomly

• Syntax:
  • .enchantRandomly()
  • .enchantRandomly(enchantments: Enchantment | Tag | Enchantment[])
  • LootFunction.enchantRandomly()
  • LootFunction.enchantRandomly(enchantments: Enchantment | Tag | Enchantment[])

LootEntry.of("minecraft:emerald_ore").enchantRandomly()

LootEntry.of("minecraft:emerald_ore").enchantRandomly(["minecraft:fortune", "minecraft:unbreaking"])

enchantWithLevels

• Syntax:
  • .enchantWithLevels(levelRange: NumberProvider)

LootEntry.of("minecraft:netherite_sword").enchantWithLevels([20, 39])

enchant

• Syntax:
  • .enchant(add: boolean, (builder) => { ... })
  • .enchant((builder) => { ... })
  • LootFunction.enchant(add: boolean, (builder) => { ... })
  • LootFunction.enchant((builder) => { ... })

The builder has a method .withEnchantment(enchantment: id, level: NumberProvider) you can use to apply enchantments.

LootEntry.of("minecraft:netherite_sword").enchant(builder => {
    builder.withEnchantment("minecraft:sharpness", [4, 5])
    builder.withEnchantment("minecraft:unbreaking", 3)
    builder.withEnchantment("minecraft:knockback", 2)
    builder.withEnchantment("minecraft:mending", 1)
})

addLore

• Syntax:
  • .addLore(lore: Component)
  • LootFunction.addLore(lore: Component)

LootEntry.of("minecraft:emerald_ore").addLore("Enchanted")

replaceLore

• Syntax:
  • .replaceLore(lore: Component)
  • LootFunction.replaceLore(lore: Component)

LootEntry.of("minecraft:emerald_ore").replaceLore("Enchanted")

damage

• Syntax:
  • .damage(damage: NumberProvider)_{, see NumberProvider}
  • LootFunction.damage(damage: NumberProvider)

LootEntry.of("minecraft:diamond_sword").damage(5)

LootEntry.of("minecraft:diamond_sword").damage([5, 10])

simulateExplosionDecay

• Syntax:
  • .simulateExplosionDecay()
  • LootFunction.simulateExplosionDecay()

LootEntry.of("minecraft:diamond_sword").simulateExplosionDecay()

smelt

• Syntax:
  • .smelt()
  • LootFunction.smelt()

LootEntry.of("minecraft:diamond_sword").smelt()

toggleTooltips

Allows to toggle rendering tooltips for specific DataComponents

• Syntax:
  • .toggleTooltips(data: { componentId: boolean })
  • LootFunction.toggleTooltips(data: { componentId: boolean })

LootEntry.of("minecraft:diamond_boots").toggleTooltips({
    "minecraft:enchantments": false,
    "minecraft:trim": true,
})

jsonFunction

• Syntax:
  • .jsonFunction(json)
  • LootFunction.fromJson(json)

LootEntry.of("minecraft:diamond_sword").jsonFunction({
    function: "minecraft:limit_count",
    limit: {
        max: 5.0,
        min: 1.0,
    },
})