In this tutorial, I will add a subbiome called "route 1" and make it spawn lvl 2-5 rattatas and pidgeys, and also remove rattata and pidgey spawns from any other locations.

Location selection in Pokecube uses a json object called a SpawnRule, this is used for location specific spawning, evolution, etc. Below I will discuss the general structure of these.

Here is an example of a spawns json

{
  "values":{
    "types":"mountain,cave",
    "typesBlacklist":"wet"
  }
}

This example will match a location which is of types mountain and cave, and not wet.

Below is a list of accepted values, and what they will do. Any below that are a list, will be separated by commas, like in types in the example above

• types - list of types which are all required to be valid

• typesBlacklist - list of types which, if present, will invalidate

• category - list of specific biomes, any biome matching will be listed as allowed

• biomesBlacklist - list of specific biomes, any biome matching will invalidate

• biomes - list of biome categories, any biome matching will be listed as allowed

• categoryBlacklist - list of biome categories, any biome matching will invalidate

• structures - list of structures which are required for spawning in

• noStructures - list of structures which will invalidate

• command - will apply whatever this is as a /pokemake argument to a pokemob as it spawns in

• day* - valid during the day time

• night* - valid at night

• dust* - valid at dusk

• dawn* - valid at dawn

• air - air is the material to spawn in (default true)

• water - water is the material to spawn in (default false)

• minLight - needs at least this much light to spawn (0-1, default 0)

• maxLight - light must be less than or equal this to spawn (0-1, default 1)

• weather - Specifies a list of weathers required for valid, defaults to not caring

• noWeather - Specifies a list of weathers which will invalidate the rule

* if none of these 4 are present, the rule will be valid at all times

These are a vanilla minecraft identification of biomes, the options are as follows:

none
taiga
extreme_hills
jungle
mesa
plains
savanna
icy
the_end
beach
forest
ocean
desert
river
swamp
mushroom
nether

For the types related fields, there are two different objects checked for validity. First, the Forge Biome Dictionary is checked. The list of built in types can be found here: https://github.com/MinecraftForge/MinecraftForge/blob/c3e84646db70f518dd0b37a8fcfc42cb814d7ba8/src/main/java/net/minecraftforge/common/BiomeDictionary.java#L288-L366

These will be checked first. If the listing does not match any of the Biome Types, then it will be assumed to be a Subbiome instead, and if not present, a Subbiome for the name will be added.

Spawn rules then generally have an additional set of values, for specifying rates, numbers, etc, and are as follows:

• min - minimum number in a spawn pack (default 2)
• max - maximum number in a spawn pack (default 4)
• rate - chance of spawn succeeding if selected (default 0, range: 0-1)
• level - override level for the spawn
• variance - override variance function for the spawn

There are example datapacks located at https://github.com/Pokecube-Development/Pokecube-Issues-and-Wiki/tree/1.16/example_datapacks which can help show how to create the datapack, and how to set the json files. These packs go in /config/pokecube/datapacks/ and require a reboot to apply

If an item is renamed subbiome-><name>, then it can be used as a subbiome setter, and will apply the subbiome <name>

This works by sneak right clicking 1 corner to set, then sneak right clicking the other corner. The volume in between will be set as the selected subbiome.

Note that to sync to the f3 menu, you may need to open the watch or pokedex's interface in that chunk