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

{
  "items": [
    {
      "default": {
        "count": {
          "max": 2
        },
        "item": "prismarine_shard"
      }
    },
    {
      "default": {
        "count": 1,
        "item": [
          {
            "chance": 0.4,
            "value": "raw_fish"
          },
          {
            "chance": 0.4,
            "value": "prismarine_crystals"
          }
        ]
      }
    },
    {
      "default": {
        "count": 1,
        "item": "raw_fish",
        "data": "net.glowstone.util.loot.LootingUtil.randomFishType()"
      },
      "conditions": [
        {
          "condition": "ENTITY_ONFIRE",
          "item": "cooked_fish"
        }
      ]
    }
  ],
  "experience": {
    "count": 10
  }
}