Item Modification

Modifying existing items

You can change properties of existing items:

ItemEvents.modification(event => {
  event.modify('minecraft:ender_pearl', item => {
    item.maxStackSize = 64
    item.fireResistant = true
    item.rarity = 'UNCOMMON'
  })

  event.modify('minecraft:ancient_debris', item => {
    item.rarity = 'RARE'
    item.burnTime = 16000
  })

  event.modify('minecraft:turtle_helmet', item => {
    item.rarity = 'EPIC'
    item.maxDamage = 481
    item.craftingRemainder = Item.of('minecraft:scute').item
  })
})

You can find full list of MutableItem properties here.

#Tool Defaults

Tier	`level`	`maxDamage`	`digSpeed`	`attackDamage`	`enchantmentValue`
Wood	0	59	2	0	15
Stone	1	131	4	1	5
Iron	2	250	6	2	14
Diamond	3	1561	8	3	10
Gold	0	32	12	0	22
Netherite	4	2031	9	4	15

attackDamage is a bonus modified by the tool type value, not the final value

#Armor Defaults

All boxes with multiple values are formatted head | chest | legs | feet.

Tier	`maxDamage`				`armorProtection`				`armorToughness`	`armorKnockbackResistance`
Leather	65	75	80	55	1	2	3	1	0	0.0
Chain	95	225	240	165	1	4	5	2	0	0.0
Iron	195	225	240	165	2	5	6	2	0	0.0
Gold	91	105	112	77	1	3	5	2	0	0.0
Diamond	429	495	528	363	3	6	8	3	2	0.0
Turtle	325	-	-	-	2	-	-	-	0	0.0
Netherite	481	555	592	407	3	6	8	3	3	0.1
Elytra	-	432	-	-	-	0	-	-	0	0.0

Turtle only has helmet slot and Elytra only has chestplate slot.

#Tier

Broken at the moment! Use the non tier methods instead.

#Tools

ItemEvents.modification(event => {
  event.modify('minecraft:golden_sword', item => {
    item.tier = tier => {
        tier.speed = 12
        tier.attackDamageBonus = 10
        tier.repairIngredient = '#forge:storage_blocks/gold'
        tier.level = 3
    }
  })

  event.modify('minecraft:wooden_sword', item => {
    item.tier = tier => {
        tier.enchantmentValue = 30
    }
  })
})

You can find full list of MutableToolTier properties here.

#Armor

Doesnt actually exist/work at the moment. Sorry.

#Food

ItemEvents.modification(event => {
  event.modify('minecraft:diamond', item => {
    item.foodProperties = food => {
        food.hunger(2)
        food.saturation(3)
        food.fastToEat()
        food.eaten(foodData => foodData.player.tell('you ate')) // this is broken, use ItemEvents.foodEaten instead.
    }
  })

  event.modify('minecraft:pumpkin_pie', item => {
    item.foodProperties = null // make pumpkin pies inedible
  })
})

You can find full list of FoodBuilder methods here.