Stop Mob Spawn

Players who want a clean slate for a new modpack usually have to set spawn rules by hand in a configuration file, and the result is often still incomplete. Stop Mob Spawn blocks spawning of vanilla mobs from the start, without any setup, and it leaves modded entities untouched. Total overhauls that remove the default creatures are the main use, since the game world then has no leftover vanilla life to break the intended atmosphere.

The mod cancels spawning for most mobs added by other mods, so those creatures do not appear either. A few exceptions protect progression: Illagers are allowed a one-tick delay so raids are not broken, the Wither is defeated automatically so a Nether star can still be obtained, and the Ender Dragon is defeated automatically so players can leave the End dimension and avoid a soft lock. It also disables structures and can be turned on at world creation, which Minecraft already offers as a setting.

The mod is published for NeoForge only, and it is client and server, so the server and every player need it. Its own release is 1.0.2 for 26.1.2, and files exist for 1.21.4, 1.21.8 and 26.1.2. It is released under All rights reserved and is not open source, so the code cannot be reused in other projects.