Mobs Not Spawning In Minecraft Java 1.16.1 Creative Mode [closed]

Solution 1:

You're on Peaceful mode.

If the player is on Peaceful mode or spawn-monsters is set to false in a server's server.properties file, hostile mobs won't spawn.

There are 2 outcomes for when 1 of the conditions mentioned above is met:

  1. Not spawning at all
  2. Despawning in a split second

The first outcome is for when you try to use spawners, in which hostile mobs won't spawn, no matter what lighting level you are on.

The second outcome is for when you try to use ways such as commands or spawn eggs, in which you'll see the mob spawn, but then despawn in a split second. This is more common than the other since spawners are rarely ever used for maps or are rarely ever encountered in survival, which in most cases the player or the server doesn't happen to be meeting any of the conditions above.