Limit Spawns Plugin: Controlling Mob Density
How Mob Limits Work
Limit Spawns Plugin keeps your server from slowing down by preventing too many mobs from grouping in one place. It checks a set area around each player and blocks new animals or monsters from appearing once that area is already crowded.
By default, the plugin checks a radius of 50 blocks in every direction and caps animals at 25 per area. This applies to friendly animals, hostile monsters, Nether creatures, End mobs, and even the Wither. Unknown or unsupported mobs are ignored, so they remain unaffected.
Configuration
You can change the checking radius to be larger or smaller depending on your needs. You can also adjust the maximum number of mobs allowed within that space. To disable a limit for a specific mob, set its limit to a negative number such as -1. This lets you fine-tune spawn control without editing the mod itself.