So I am building a zoo in a modded Creative single player mode with a goal in mind to have zero mobs (hostile and passive) unable to spawn in the wild. I would like to spawn said mobs manually, hostile included. The end goal is to have no mobs be able to spawn in when I login other than the ones I had spawned in manually. I am having trouble getting this to work under certain parameters which are:
A ) Game mode must be kept in Creative. No peaceful mode either due to the need of hostile entities to be spawnable through spawn eggs.
B ) When I login into the world, I would like no "wild" mobs spawning at all.
I have tried using commands, ini changes, command blocks, etc. but the above goal seems to be not doable. I have been using the commands /gamerule doMobSpawning false and /kill @e[type=!Player] after each login but that can't be the end solution due to the zoo dynamic. Hostile mods still end up spawning for example despite the game rule being altered. The game rule also doesn't seem to affect some modded mobs either. I am basically at a loss right now and not really sure if what I want can be done currently. I was thinking this could be fixed using nametags but I'm not sure where I could go with that.
If anyone knows any sort of command, ini changes, game rule options I could use to help me out - it'll be greatly appreciated, thanks!
/gamerule doMobSpawning false should always work. You don't need to do it every login. It works once and sticks. It's case sensitive but you capitalized it correctly here so I assume you're doing it right.
Mo Creatures (which I'm guessing is your modded mobs mod) also seems to be very problematic and can break this spawn rule. Disable that mod and see if it works. If it's fixed, there's your issue, you know what to Google now at least. You can change the spawn rate of Mo Creatures mods in its settings with Notepad, though many people say this doesn't work either. Try also disabling every other plugin to check for conflicts.
But there's no solution to this issue that I can find, so chances are you either have to disable Mo Creatures or deal with the mobs spawning. Or post/do more research here. https://www.mocreatures.org/forum