Greetings to everyone! The problem would be that the PureEntityX plugin available for the Pocket Mine server is not really good. It would be nice to have the VanillaEntityAI plugin in, because that's how it works in vain if the mobs don't spawn! Also, it would be nice if the NukkitX server was included with plugin support! 
The Plugin link: https://poggit.pmmp.io/p/VanillaEntityAI/1.0.0-alpha5
