Attribute Effect

Effect Type: Attribute

• Attribute Name, required, generic.attackDamage
• Modifier Amount, required, Random Value Range
• Modifier Operation, required, 0=ADD, 1=MULT_BASE, 2=MULT_TOTAL

For a more detailed explanation of the operations, see Minecraft Wiki

Example:

"Effects": [
    {
      "Effect Type": "Attribute",
      "Attribute Name": "generic.attackDamage",
      "Modifier Amount": "[2 : 3] int",
      "Modifier Operation": 0,
      "Equipment Slot Type": "HAND"
    }
]

Note: Some attribute effects will only apply during attacks.

• Reach Distance, Attack Damage and Attack Speed on weapons will only apply when attacking
• Armor and Armor Toughness on armor will only apply when getting attacked