How to Stop Mobs Spawning in a Specific Area with In Control

In Control works by matching spawn attempts against rules you write in its config files. To block spawning in a region, you write a rule that matches the mob and the location, then deny it.

Write the rule

Open the In Control config folder and find the spawn rules file. Rules are written as JSON objects. A blocking rule needs a mob filter (or a list of mobs), a dimension filter, and a biome or position-based filter, plus a result of deny. For a fixed area, use a position filter with the corner coordinates of the region you want protected. If you only want to protect a biome, use the biome filter instead — it is simpler and needs no coordinates.

Test and refine

After saving, reload the config (or restart the game) and walk into the area at night. If mobs still appear, check that your dimension id matches the world you are in and that the coordinates are in the right order. Remember that In Control only affects natural spawn attempts — mobs spawned by spawners, commands, or structures will still appear. To cover those, add separate rules targeting the spawner-spawned mobs, or use a structure filter if the source is a specific structure.