I want to ask if any mod is functional: after I kill all the monsters in the area, then there are new monsters appearing? I mean, it will be like an online game, I don’t have to move but just need to stand one place to kill monsters one after another. Sorry if my English is poor. Thank you.
Welcome to the forum. 
I don’t know of any mods that have monsters constantly spawning around you.
no there are no mods like this afaik, you can play crucible though, that’s kinda like what you want.
Thanks for your help.