On your Multicraft control panel, stop your server. Navigate to Files > Config Files > Bukkit.yml. Adjusting the settings highlighted in blue will adjust the spawn rates of your mobs. These numbers are the maximum amount of mobs that can be spawned in your world at any one time.

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My conclusion is that I need to change the biomes to change spawn rates. I can access the biomes using either BiomeRegistry or ForgeRegistries.BIOMES. I see 2 approaches here: Replace the map of biomes completely. Sadly its register method is private so I cannot add new biomes to replace the existing ones. I also read here that removing them is apparently not …

Well, here is an example: ModLoader.addSpawn(YOURENTITY.class, 25, 1, 3); The first number is the percent of the mob spawning against other mobs, the second number is the minimum group your mob can spawn in, and the third number is the maximum group number your mob can spawn in.

1.14 and newer versions are known to have serious problems regarding mob spawning which is probably the cause for your issue. Right now 1.14.2 is known to be quiet stable regarding mob spawning. Please try to use that version. You can switch your version on the software page:

Increasing mob rates in general. level 1. BrunoSupremo. · 6 yr. ago. One thing using commands blocks is to double the mobs. /execute @e [type=Zombie] ~ ~ ~ summon Zombie ~ ~ ~. Run this and all Zombies will duplicate. Put in a slow clock to …

How to Increase Spawn Rates on any Pixelmon Server | Minecraft: Pixelmon Guide – YouTube.

Make sure the 9x3x9 area around the spawner is dark and does not contain any mobs. Any mobs spawned by the spawner should leave the 9x9x9 (Java) or 16x10x16 (Bedrock) area around the spawner before the next spawn cycle happens, i.e. within 10 seconds. Light up the nearby area. And the only dark space be the spawner.

Try set ticks-per monster-spawn to 1, if not 1 already. Then the spawn radius for monsters to be the same as your view distance. I just did this myself. Set spawn radious from 4 to 7 since that is my view distance. I also upped the monster cap a bit. I am not sure if it improved anything, though :/

This command will set a Minecraft world’s spawn point to the current location of the player who issued the command. This must be used in-game and can only be done by a server operator. (Related article: Giving Operator to a Player) When used with coordinates X, Y, and Z, the spawn point will be changed to the specified coordinates. This command can be used in the server …

The mob spawn cap for natural spawns can be adjusted by enabling the Change Mob Quantities feature. This feature is off by default so you would have to specifically enable it. During the normal world tick Minecraft will spawn mobs based on their class and the class mob cap.

How to adjust mob spawning rates

1. On your Multicraft control panel, stop your server.
2. Navigate to Files > Config Files > Bukkit.yml
3. In this file, you will find the following settings:
   delay-chunk-unloads-by: 30s
   spawn-limits:
   monsters: 70
   animals: 10
   water-animals: 15
   water-ambient: 20
   ambient: 15
   chunk-gc:
   period-in-ticks: 600
4. Adjusting the settings highlighted in blue will adjust the spawn rates of your mobs. These numbers …