This datapack allows you to modify spawners in a user-friendly way!

In order to give or take permission to edit spawners, run the following command:
/tag <player> (add|remove) bccsc_enabledGive yourself a spawner with:
/give @s spawner
Changing mob type
Simply click with any spawn egg on the spawner block.

Cloning the spawner
Spawners are one of the few blocks that can't be copied by CTRL + Pick Block Key. So in order to clone a spawner, throw another spawner item on top. The spawner copy will appear in the inventory of the closest player.

Modifying the spawner
Simply stand on top of the spawner. A chest will spawn.
Open the chest to access the Custom Spawner Creator GUI. The top two rows are page specific. The bottom row contains the following buttons:

• Discard & Exit: Makes the chest disappear.
• Load Inventory: Change armor, hand items and their drop chances.
• Load Potions: Add any potion effect of any level to the mob.
• Load Settings: Modify any spawner setting.
• Trash: Place any items in this slot to make them disappear.
• Save: Save the currently open page.

Clicking any of the load buttons will result in that page being opened.
Make sure to save before going to the next page.
Pages:

• Inventory
  • Put armor and weapons in the top row. If the slot is empty, a piece of paper will appear telling you what kind of armor or weapon is expected.
  • Supports enchantments
  • Supports off-hand items
  • To give the mob a name, place any named helmet or nametag in the helmet slot.
  • The amount of items in the slots below indicate the drop chances in units of 5%. By default, this amount is 20 (100%).
  • Armor and weapons still affect mobs that don't show them, like silverfish or slime.
• Potions
  • The top row contains the potion ID.
  • The slots below indicates the potion level for the ID above, where 0 items = level 1.
  • Supports effects that are not available as potion. (Examples: Glowing, Levitation, Health Boost, Absorption, Speed 5, Jump Boost 10, Regeneration 3)
  • Potions will last forever for non-instant effects.
  • Mobs will not show the potion particles.
• Settings
  • Place any amount of items in the slots on the second row to change the setting indicated by the piece of paper above.
  • Amount: Amount of mobs spawned each cycle.
  • Range: The horizontal radius of the square spawn area. Mobs spawn more towards the center.
  • Min Delay: The minimum delay between spawn cycles.
  • Max Delay: The maximum delay between spawn cycles.
  • Max Mobs: The maximum amount of mobs of the current type in the spawn area.
  • Player Activation Range: At least one player must be in this spherical area in order to activate the spawner.

Important Note
Do not use with custom spawners created by other data packs, map makers or mods. The datapack might show unexpected behaviour if these kind of spawners are edited.

Also, feel free to send me pictures or videos of custom mobs you created. Don't forget that you can use a resource pack to make your imaginary mob type fit right in.

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