Spectrum's Fishing Rods (in addition to being able to fish in more than just water) use a mechanism called Entity Fishing. It does exactly what it says on the tin: when fishing, you have a chance of catching a living entity! This chance can be increased with the "Big Catch" enchantment.

You can specify which entities are fished by placing json files in the directory <data_pack_or_mod_name>/entity_fishing/.

Properties:

• {} location: Predicates that have to pass for this fishing entry to evaluate
  • (FluidPredicate) fluid: The fluid that can contain fishable entities (as via fluid id or fluid tag).
  • (BiomePredicate) biome: The biomes in which these entities can be fished.
  • (LightPredicate) light: The block and sky light in which these entities can be fished.
  • (DimensionPredicate) dimension: The dimensions in which these entities can be fished
  • (MoonPhasePredicate) moon_phase: The moon phase these entities can be fished in
  • (TimeOfDayPredicate) time_of_day: The time of day when these entities can be fished.
  • (WeatherPredicate) weather: The weather in which these entities can be fished
  • (CommandPredicate) command: An arbitrary command to test against
• (float) chance: The base chance to fish an entity instead of the usual loot. This is multiplied by the level of the Big Catch enchantment if the rod is enchanted.
• {} entities: A weighted list of entity entries that can be fished.
  • (Identifier) id: The entity to be fished
  • (int) weight: The relative likelihood of this entry being selected
  • (String) nbt: A standard NBT string to apply to the entity
  • (JsonNBT) nbt: An NBT string using Spectrum's custom JsonNBT format that will be applied to the entity.

Example: Dragonrot

{
  "location": {
    "fluid": {
      "tag": "spectrum:dragonrot"
    },
  },
  "chance": 0.5,
  "entities": [
    {
      "id": "minecraft:pufferfish",
      "weight": 10
    },
    {
      "id": "minecraft:creeper",
      "weight": 5,
      "nbt": {
        "powered": true
      }
    },
    {
      "id": "minecraft:cod",
      "weight": 2
    },
    {
      "id": "minecraft:salmon",
      "weight": 2
    }
  ]
}