Loot and Trade Table Functions
Both loot and trade tables share a similar same function set. While most work on both, some only work within a specific type. There are limitations to loot/trade tables in general: for instance, there isn't a way to add can_place_on or can_destroy onto an item through loot or trade tables. See below for the different functions available and an example on how they can be used.
In this tutorial you will learn the following:
- A variety of loot and trade table functions and how they can modify an item.
Requirements
It's recommended that the following be completed before beginning this tutorial.
Enchanting
These different enchanting functions allow you to set unique enchanting parameters.
enchant_book_for_trading (trade table only)
This function enchants a book using the algorithm for enchanting items sold by villagers. It takes four parameters: base_cost, base_random_cost, per_level_random_cost, and per_level_cost.
{
"type": "item",
"name": "minecraft:book",
"quantity": 1,
"functions": [
{
"function": "enchant_book_for_trading",
"base_cost": 2,
"base_random_cost": 5,
"per_level_random_cost": 10,
"per_level_cost": 3
}
]
}
At this time, defining these parameters won't affect the enchantment received. Currently, the default values above are hard-coded. In the future, you'll be able to tweak these values to help narrow down what enchantments and enchantment levels this function results in.
enchant_random_gear
Enchants an item utilizing the same algorithm used while enchanting equipment vanilla mobs spawn with. Takes a chance modifier to manipulate the algorithm. Note that a chance modifier of 1.0 doesn't mean a 100% chance that gear will become enchanted. Rather, the chance is modified based on the difficulty. On Peaceful and Easy difficulties, the chance will always be 0% no matter what. On Hard difficulty, a chance of 1.0 will be 100%, but the chance is roughly 2/3 that on Normal difficulty.
{
"type": "item",
"name": "minecraft:chainmail_boots",
"weight": 1,
"functions": [
{
"function": "enchant_random_gear",
"chance": 0.25
}
]
}
Increasing chance to a number higher than 1.0 can help to bypass the decrease in chance with Normal difficulty. For example, setting chance to 2.0 will always enchant the item on both Normal and Hard difficulty.
enchant_randomly
Generates a random enchantment that is compatible with the item. Supports the optional treasure boolean (true/false) to allow treasure enchantments to be toggled on and off. Treasure enchantments are enchantments that cannot be obtained through the enchanting table, including Frost Walker, Mending, Soul Speed, Curse of Binding, and Curse of Vanishing.
{
"type": "item",
"name": "minecraft:leather_helmet",
"weight": 1,
"functions": [
{
"function": "enchant_randomly",
"treasure": true
}
]
}
enchant_with_levels
Applies an enchantment as if it were enchanted through an enchanting table using a minimum and maximum XP level defined through the levels parameter. The treasure boolean (true/false) will allow treasure-only enchantments to be used. Treasure enchantments are enchantments that cannot be obtained through the enchanting table, including Frost Walker, Mending, Soul Speed, Curse of Binding, and Curse of Vanishing.
{
"type": "item",
"name": "minecraft:diamond_sword",
"weight": 1,
"functions": [
{
"function": "enchant_with_levels",
"treasure": true,
"levels": {
"min": 20,
"max": 39
}
}
]
}
set_potion
This function sets the potion type of compatible items with a potion id.
{
"type": "item",
"name": "minecraft:potion",
"weight": 1,
"functions": [
{
"function": "set_potion",
"id": "strong_regeneration"
}
]
}
specific_enchants
This function allows you to set a list of specific enchantments on an item. It also allows you to apply enchantments to items that wouldn't normally be enchantable in-game.
{
"type": "item",
"name": "minecraft:stick",
"weight": 1,
"functions": [
{
"function": "specific_enchants",
"enchants": [
"knockback",
"fire_aspect"
]
}
]
}
You can also define the enchantments as objects to specifically define an enchantment level. Max enchantment levels are hard-coded and can't be overwritten.
{
"type": "item",
"name": "minecraft:stick",
"weight": 1,
"functions": [
{
"function": "specific_enchants",
"enchants": [
{
"id": "knockback",
"level": 1
},
{
"id": "unbreaking",
"level": 3
}
]
}
]
}
Modifying items
The following set of functions allow you to modify the results in different ways, such as setting how many of an item is returned, setting its data value, or even setting the name and lore of an item.
looting_enchant (loot table only)
This function allows you to modify the count of how many items are returned when an entity is killed by an item with the looting enchantment. Due to that, it only works with loot tables, and only if that loot table is called by the death of an entity.
{
"type": "item",
"name": "minecraft:stick",
"weight": 1,
"functions": [
{
"function": "looting_enchant",
"count": {
"min": 0,
"max": 1
}
}
]
}
random_aux_value
Similar to random_block_state, this allows you to pick a random auxiliary value for an item. The following example will result in a randomly-colored dye.
{
"type": "item",
"name": "minecraft:dye",
"weight": 1,
"functions": [
{
"function": "random_aux_value",
"values": {
"min": 0,
"max": 15
}
}
]
}
random_block_state
This allows you to randomize the block state of the resulting item. For instance, the following example code can drop stone (0), granite (1), polished granite (2), diorite (3), polished diorite (4), or andesite (5).
{
"type": "item",
"name": "minecraft:stone",
"weight": 1,
"functions": [
{
"function": "random_block_state",
"block_state": "stone_type",
"values": {
"min": 0,
"max": 5
}
}
]
}
random_dye
This function affects the colors of the random leather items supplied by a leather worker.
Example:
"gives": [
{
"item": "minecraft:leather_helmet",
"quantity": 1,
"functions": [
{
"function": "random_dye"
}
]
}
]
set_actor_id
This function only works with a spawn egg and is used to set the entity ID of that spawn egg.
{
"type": "item",
"name": "minecraft:stone",
"weight": 1,
"functions": [
{
"function": "set_actor_id",
"id": "sample:cool_entity"
}
]
}
You can also inherit the entity ID of the entity that's associated with that loot table (i.e., make a rabbit drop a rabbit spawn egg) by omitting the id.
{
"type": "item",
"name": "minecraft:spawn_egg",
"weight": 1,
"functions": [
{
"function": "set_actor_id"
}
]
}
Be aware that if you use set_actor_id on a chest's loot table and omit the id value, it will generate the spawn egg of whatever opens the chest (the player). A player spawn egg will spawn a "player" that just stands around and throws up Molang errors (since it's trying to use the player's behavior file as well as the player's controllers). If you break a chest containing a loot table that uses an inherited id from set_actor_id, it drops a default spawn egg that doesn't spawn anything.
set_banner_details
This function only works on banners and currently only supports a banner type of 1. A banner type of 1 results in an illager banner.
{
"type": "item",
"name": "minecraft:banner",
"weight": 1,
"functions": [
{
"function": "set_banner_details",
"type": 1
}
]
}
set_book_contents
This function allows you to set the contents of a book.
{
"type": "item",
"name": "minecraft:written_book",
"functions": [
{
"function": "set_book_contents",
"author": "Steve",
"title": "Creator Woes",
"pages": [
"Once upon a time there were some marketplace partners that had to edit items using NBT. And it made them sad.",
"Then the Bedrock team added the ability to customize items from JSON and everyone rejoiced."
]
}
]
}
You can also use rawtext to localize the content of the book. When using rawtext, remember to always escape (\) special characters like " and \.
{
"type": "item",
"name": "minecraft:written_book",
"functions": [
{
"function": "set_book_contents",
"author": "Steve",
"title": "Creator Woes",
"pages": [
"{\"rawtext\":[ {\"translate\":\"custom.book.page.1\"}]}",
"{\"rawtext\":[ {\"translate\":\"custom.book.page.2\"}]}"
]
}
]
}
Be aware that you can only use rawtext on the book's contents (pages) at the timing of writing this — rawtext does not work for the author or title tags.
set_count
Sets the quantity of items returned by setting the count value. It could either be an exact number like this example:
{
"type": "item",
"name": "minecraft:stone",
"weight": 1,
"functions": [
{
"function": "set_count",
"count": 5
}
]
}
Or it can be within a min/max range:
{
"type": "item",
"name": "minecraft:stone",
"weight": 1,
"functions": [
{
"function": "set_count",
"count": {
"min": 1,
"max": 6
}
}
]
}
set_damage
Sets the percentage of durability remaining for items that have durability by setting the damage value. 1.0 is 100% of durability remaining (undamaged) while 0.0 is no durability remaining.
You can either set it to an exact durability like in the following example where we set the item to have 50% durability remaining.
{
"type": "item",
"name": "minecraft:iron_leggings",
"weight": 1,
"functions": [
{
"function": "set_damage",
"damage": 0.5
}
]
}
Or you can define a min/max amount the game will randomly choose from. The next example sets the durability to somewhere between 30% and 90% remaining.
{
"type": "item",
"name": "minecraft:iron_leggings",
"weight": 1,
"functions": [
{
"function": "set_damage",
"damage": {
"min": 0.3,
"max": 0.9
}
}
]
}
set_data
Sets the data value of a block or item to an exact id. This is useful for things like returning a specific potion or specific color of item. It also allows you to return different block values, like a specific log type.The following example will result in a polished diorite block.
{
"type": "item",
"name": "minecraft:stone",
"functions": [
{
"function": "set_data",
"data": 4
}
]
}
set_data_from_color_index
Inherits the data value of the resulting item from the associated entity's color index. An in-game example would be a pink sheep dropping pink wool on death. If the associated entity doesn't have a color index set (or it's used inside a chest's loot table), it will always result in a data value of 0.
{
"type": "item",
"name": "minecraft:wool",
"weight": 1,
"functions": [
{
"function": "set_data_from_color_index"
}
]
}
set_lore
This function allows you to set the lore of an item. Each line within the lore object represents a single line of text. There's currently no support for rawtext.
{
"type": "item",
"name": "minecraft:stick",
"weight": 1,
"functions": [
{
"function": "set_lore",
"lore": [
"Big Stick has been handed down",
"for generations from King to Prince",
"until it went missing four score ago"
]
}
]
}
set_name
This function allows you to set the name of an item. There's currently no support for rawtext.
{
"type": "item",
"name": "minecraft:stick",
"weight": 1,
"functions": [
{
"function": "set_name",
"name": "Big Stick"
}
]
}
Miscellaneous
The following contains functions that don't fit anywhere else.
exploration_map
Transforms a normal map into a treasure map that marks the location of hidden treasure. The destination value defines what type of treasure map they receive.
{
"type": "item",
"name": "minecraft:map",
"weight": 1,
"functions": [
{
"function": "exploration_map",
"destination": "buriedtreasure"
}
]
}
You could currently choose from the following destinations:
| Destination |
|---|
| buriedtreasure |
| endcity |
| fortress |
| mansion |
| mineshaft |
| monument |
| pillageroutpost |
| ruins |
| shipwreck |
| stronghold |
| temple |
| village |
fill_container
This function allows you to define the loot table for a chest. When the item is generated and the player places it, it will be full of the contents defined inside the referenced loot table.
Loot tables for chests are generated at the time of opening or breaking. Consider it a Schrödinger's box. The content of the chest isn't decided until you look inside.
{
"type": "item",
"name": "minecraft:chest",
"functions": [
{
"function": "fill_container",
"loot_table": "loot_tables/chests/simple_dungeon.json"
}
]
}
It's advisable to always use set_name to give the chest a name when using fill_container. If you don't, the resulting chest won't look any different in the player's inventory than a normal empty chest would.
furnace_smelt (loot table only)
If the item to return has a smelted crafting recipe and the loot table is triggered by an entity killed with fire (Fire Aspect, flint and steel, lava, etc), the result will be the smelted version of the item. Due to these requirements, this function does not work in villager trades or with chests. This function only works if used in conjunction with the minecraft:loot behavior.
The following example will drop a stone block if the entity is killed by fire or cobblestone if not.
{
"type": "item",
"name": "minecraft:cobblestone",
"weight": 1,
"functions": [
{
"function": "furnace_smelt"
}
]
}
trader_material_type
This function affects the type of items a fisherman wants to trade for other items, such as a boat.
"wants": [
{
"item": "minecraft:boat",
"quantity": 1,
"price_multiplier": 0.05,
"functions": [
{
"function": "trader_material_type"
}
]
}
Multiple functions
Multiple functions can be defined. Here's an example of combining two functions together. In this example, this entry will return between one and three Potions of Healing.
{
"type": "item",
"name": "minecraft:potion",
"weight": 1,
"functions": [
{
"function": "set_count",
"count": {
"min": 1,
"max": 3
}
},
{
"function": "set_data",
"data": 21
}
]
}
Multiple functions can even be multiple of the same function, but if there's a conflict between those functions, the last to be defined will win.
For example, using multiple set_count functions, like with the example below, will result in only the last of the duplicates being used, causing the item to have a count between 5 and 7 rather than between 1 and 3.
{
"type": "item",
"name": "minecraft:potion",
"weight": 1,
"functions": [
{
"function": "set_count",
"count": {
"min": 1,
"max": 3
}
},
{
"function": "set_count",
"count": {
"min": 5,
"max": 7
}
}
]
}