PREREQUISITES
You must first understand how to create an item, which you can then turn into a spawn egg.
Spawn eggs are special items that, when used, spawn their corresponding mob. You can register one with the register method from your items class, by passing SpawnEggItem::new to it.
java
public static final SpawnEggItem CUSTOM_SPAWN_EGG = register(
"custom_spawn_egg",
SpawnEggItem::new,
new Item.Properties().spawnEgg(EntityType.FROG)
);
ItemGroupEvents.modifyEntriesEvent(CreativeModeTabs.SPAWN_EGGS)
.register(itemGroup -> itemGroup.accept(ModItems.CUSTOM_SPAWN_EGG));1
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There are still a few things to do before it's ready: you must add a texture, an item model, a client item, a name, and add the spawn egg to the appropriate creative tab.
Adding a Texture
Create the 16x16 item texture in the assets/example-mod/textures/item directory, with the same file name as the id of the item: custom_spawn_egg.png. An example texture is provided below.
Adding a Model
Create the item model in the assets/example-mod/models/item directory, with the same file name as the id of the item: custom_spawn_egg.json.
json
{
"parent": "minecraft:item/generated",
"textures": {
"layer0": "example-mod:item/custom_spawn_egg"
}
}1
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Creating the Client Item
Create the client item JSON in the assets/example-mod/items directory, with the same file name as the id of the item model: custom_spawn_egg.json.
json
{
"model": {
"type": "minecraft:model",
"model": "example-mod:item/custom_spawn_egg"
}
}1
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Naming The Spawn Egg
To name the spawn egg, the translation key item.example-mod.custom_spawn_egg must be assigned a value. This process is similar to Naming The Item.
Create or edit JSON file at: src/main/resources/assets/example-mod/lang/en_us.json and put in the translation key, and its value:
json
{
"item.example-mod.custom_spawn_egg": "Custom Spawn Egg"
}1
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Adding To A Creative Mode Tab
The spawn egg is added to the spawn egg CreativeModeTab in the initialize() method of the items class.
java
ItemGroupEvents.modifyEntriesEvent(CreativeModeTabs.SPAWN_EGGS)
.register(itemGroup -> itemGroup.accept(ModItems.CUSTOM_SPAWN_EGG));1
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Check out Adding The Item To An Creative Mode Tab for more detailed information.





