src/main/resources/builtin/loot/entities/zombie.json

{
  "items": [
    {
      "default": {
        "count": {
          "max": 2
        },
        "item": "rotten_flesh"
      }
    },
    {
      "default": {
        "count": 1,
        "item": [
          {
            "chance": 0.025,
            "value": "iron_ingot"
          },
          {
            "chance": 0.025,
            "value": "carrot"
          },
          {
            "chance": 0.025,
            "value": "potato"
          }
        ]
      }
    }
  ],
  "experience": {
    "count": 5,
    "conditions": [
      {
        "condition": "$.isBaby()",
        "count": 12
      }
    ]
  }
}