It would be nice for sandbox packs to have the ability to restrict the MK:Ultra challenge components to dimensions by white/blacklists. This will allow a pack mater to set up an opt-in experience for players.

Other mods like InControl don't work because MKU replaces existing mobs. Ideally I'd want normal spawns in the dimension(s) marked "easy" and the MKU mobs in the dimension(s) marked "hard".

Turn off mob spawning for this mod and use the mod: Custom Mob Spawner - and you can do that. Thats what I do in my pack.