polar_bear.json

{
  "type": "minecraft:entity",
  "pools": [
    {
      "rolls": 1,
      "entries": [
        {
          "type": "item",
          "name": "minecraft:heart_of_the_sea",
          "weight": 1,
          "functions": [
            {
              "function": "set_count",
              "count": 1,
              "conditions": [
                {
                  "condition": "random_chance_with_looting",
                  "chance": 1,
                  "looting_multiplier": 0.25
                },
                {
                  "condition": "entity_properties",
                  "entity": "polar_bear",
                  "flags": [
                    {"is_baby": true}
                  ],
                  "predicate": {
                    "nbt": "{Air:0s}"
                  }
                },
                {
                  "condition": "damage_source_properties",
                  "predicate": {
                    "bypasses_armor": true,
                    "bypasses_invulnerability": false,
                    "bypasses_magic": false,
                    "source_entity": {
                      "entity": null
                    }
                  }
                },
                {
                  "condition": "alternative",
                  "terms": [
                    {
                      "condition": "location_check",
                      "predicate": {
                        "state": {
                          "waterlogged": true
                        }
                      }
                    },
                    {
                      "condition": "location_check",
                      "predicate": {
                        "block": "minecraft:water"
                      }
                    }
                  ]
                }
              ]
            }
          ]
        }
      ]
    }
  ]
}